JPH0469928B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to liquid crystal elements used in liquid crystal display elements, liquid crystal light shutters, etc., particularly liquid crystal elements using ferroelectric liquid crystal, and more specifically to improving the initial alignment state of liquid crystal molecules. This invention relates to a liquid crystal element with improved display characteristics. [Prior Art] Clark and Lagerwall have proposed a type of display element that uses the refractive index anisotropy of ferroelectric liquid crystal molecules to control transmitted light in combination with a polarizing element. (Japanese Patent Application Laid-Open No. 107216/1983, US Pat. No. 4,367,924, etc.). This ferroelectric liquid crystal generally has a chiral smectic C phase (SmC ^* ) or H phase (SmH ^* ) in a specific temperature range, and in this state, the first optical It has the property of being in either an optically stable state or a second optically stable state and maintaining that state when no electric field is applied, that is, it has bistability, and it also responds quickly to changes in the electric field. , and is expected to be widely used as high-speed and memory-type display elements. In order for an optical modulation element using this bistable liquid crystal to exhibit predetermined driving characteristics, the liquid crystal placed between a pair of parallel substrates must maintain the above two stable characteristics, regardless of the applied state of the electric field. It is necessary that the molecules be in such a state that conversion between states can occur effectively. For example, for ferroelectric liquid crystals with SmC ^* or SmH ^* phase, SmC ^* or
It is necessary to form a region (monodomain) in which the liquid crystal molecular phase having the SmH ^* phase is perpendicular to the substrate surface, and the liquid crystal molecular axes are arranged substantially parallel to the substrate surface. By the way, as a method for aligning ferroelectric liquid crystal,
Generally, a method using an alignment control film subjected to uniaxial alignment treatment such as rubbing treatment or oblique evaporation treatment is known. Most of these conventional alignment methods have been applied to ferroelectric liquid crystals having a helical structure that does not exhibit bistability. For example, the alignment method disclosed in European Patent Publication No. 91661 and Japanese Patent Application Laid-Open No. 60-230635 uses polyimide, polyamide or Orientation was controlled by a polyvinyl alcohol film. However, when the conventional alignment control film as described above is applied to control the alignment of a ferroelectric liquid crystal with a non-helical structure exhibiting bistability as announced by Clark and Lagauer, the following problems arise. It had [Problems to be Solved by the Invention] According to experiments conducted by the present inventors, the tilt angle θ( Part 3 mentioned below
The angle θ shown in the figure) is smaller than the tilt angle of the ferroelectric liquid crystal with a helical structure (the angle that is half the apex angle of the triangular pyramid shown in Figure 2 below). There was found. In particular, the tilt angle θ of a ferroelectric liquid crystal with a non-helical structure obtained by alignment using a conventional alignment control film is generally about several degrees, and the transmittance at that time is about 3 to 5% at most. . Thus, according to Clark and Lagauer, the tilt angle of a ferroelectric liquid crystal with a non-helical structure that achieves bistability should be the same as the tilt angle of a ferroelectric liquid crystal with a helical structure. However, in reality, the tilt angle θ in the non-helical structure is smaller than that in the helical structure. That is,
In order for the tilt angle θ to take the maximum tilt angle, the orientation state of the liquid crystal molecules needs to be in the uniform orientation shown in Figure 4, but in reality, each adjacent liquid crystal is aligned as shown in Figure 5. There was a problem in that it was not possible to form a sufficiently large tilt angle θ because the molecules were in a splay orientation state caused by being twisted and oriented at a twist angle α. In addition, a liquid crystal element in a splayed alignment state exhibits an optical response characteristic to a pulse signal as shown in FIG. 7, and this optical response characteristic causes flickering on the display screen when multiplexing driving is performed. The dot was hot. It is therefore an object of the present invention to solve the aforementioned problems, namely that at least two stable states;
In particular, the object of the present invention is to provide a liquid crystal element in which the tilt angle of a non-helical ferroelectric liquid crystal realizing bistability is increased, thereby improving the transmittance when the pixel shutter is opened. Another object of the present invention is to provide a liquid crystal element that does not cause flickering on the screen during multiplexing driving. That is, according to the present invention, by using a specific alignment control film, it is possible to realize a ferroelectric liquid crystal element in the uniform alignment state shown in FIG. It is possible to realize a liquid crystal element that exhibits optical response characteristics to pulse signals and does not cause flickering on the screen during multiplexing drive. The specific alignment control film used in the present invention can be formed from a modified polyvinyl alcohol resin. In particular, by using a silane modified product, a sulfoxide modified product, a sulfur modified product, an amide modified product, a 1,3-dioxane modified product, etc. as a modified product of polyvinyl alcohol resin, the ferroelectric liquid crystal in the uniform orientation state described above can be produced. element can be realized. [Means for Solving the Problem] and [Operation] That is, the present invention has a pair of parallel substrates and an arrangement of molecules forming a plurality of layers perpendicular to the planes of the pair of parallel substrates. In a liquid crystal element having a ferroelectric liquid crystal, at least one of the pair of parallel substrates is an alignment control film formed of a modified polyvinyl alcohol resin that preferentially orients the plurality of layers in one direction. This is a liquid crystal element characterized by having the following characteristics. The present invention will be explained in detail below. FIGS. 1a and 1b are cross-sectional views showing embodiments of the liquid crystal element of the present invention, respectively. The liquid crystal element shown in FIG. 1a includes a pair of upper and lower substrates 11a and 11b arranged in parallel, and transparent electrodes 12a and 12b wired to each substrate. Upper substrate 11
A ferroelectric liquid crystal, preferably a non-helical ferroelectric liquid crystal 13 having at least two stable states, is arranged between the lower substrate 11b and the lower substrate 11b. The transparent electrodes 12a and 12b described above are used to multiplex drive the ferroelectric liquid crystal 13.
It is preferable that the wires are arranged in a stripe shape, and the stripe shapes are arranged to intersect with each other. In the liquid crystal element shown in FIG. 1a, the substrates 11a and 1
1b, alignment control films 14a and 14b each formed of the above-mentioned modified polyvinyl alcohol resin.
is located. Furthermore, one of the alignment control films 14a and 14b used in the liquid crystal element shown in FIG. It is also possible. The orientation control film used at this time can be a film formed of polyimide, polyamide, or undenatured polyvinyl alcohol. Furthermore, in the present invention, as shown in FIG. 1b,
It is also possible to omit the use of the alignment control film 14b used in the liquid crystal element of FIG. 1a. In the present invention, the above-mentioned alignment control films 14a and 14
b can be given a uniaxial orientation axis. This uniaxial orientation axis can be imparted preferably by a rubbing treatment. At this time, the aforementioned uniaxial orientation axes can be parallel to each other, but they can also be made to intersect with each other. The modified polyvinyl alcohol used for the alignment control films 14a and 14b of the present invention is silicon-containing polyvinyl alcohol containing silicon element. Specific examples of these modified polyvinyl alcohols include the following. First, the structural unit represented by (- CH | OH-CH ₂ )- and the following general formula (1a), (1b) or (1c)
It consists of a film of modified polyvinyl alcohol containing a structural unit represented by any one of these. General formula (1a) (In the formula, R _1a-1 and R _1a-2 represent an alkyl group having 1 to 8 carbon atoms) General formula (1b) (In the formula, R _1b represents an alkyl group having 1 to 8 carbon atoms) General formula (1c) (In the formula, X _1c , Y _1c and Z _1c are an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or a hydroxy group, and W _1c is -O-, (-CH ₂ )- _l1 , - O(-CH ₂
) _—n1 or −O(—CH ₂ ) _—o1 O—. Also, q1
indicates 0 or 1, l1, m1 and n1 are 1 to 8
(indicates an integer of ) will be explained more specifically. Modified product of polyvinyl alcohol resin (1); Silane modified product In the formula, R _1a-1 and R _1a-2 are alkyl groups having 1 to 8 carbon atoms, and x/x+y (mol%) is 0.01 to 30 (mol%), preferably 1 to 20 (mol%). (2); Silane modified product In the formula, R _1b represents an alkyl group having 1 to 8 carbon atoms. x/x+y (mol%) is 0.01 to 30 (mol%), preferably 1 to 20 (mol%). (3); Silane modified product In the formula, X _1c , Y _1c and Z _1c are an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or a hydroxy group, and W _1c is -O-, (-CH ₂ )- _l1 , -
O(-CH ₂ )- _n1 or -O(-CH ₂ )- _o1 O-. Further, q1 represents 0 or 1, and l1, m1 and n1 are integers of 1 to 8. Moreover, x/x+y (mol%) is 0.01 to 30 (mol%), preferably 1 to 20 (mol%). The degree of modification of the modified polyvinyl alcohol resins represented by general formulas (1a) to (1c) is suitably 30 mol% or less, but preferably in the range of 1 mol% to 20 mol%. It is better to do so. In particular, in the present invention, 1 mol% to 10 mol% is suitable. In addition, its degree of polymerization is 100 to 10000, preferably
It is best to set it between 500 and 2000. In the present invention, silicon-containing polyvinyl alcohols of the aforementioned general formulas (1a) to (1c) are suitable for obtaining ferroelectric liquid crystals in a uniformly oriented state as modified polyvinyl alcohols, such as " R-
1130'', ``R-2105'' and ``R-2130'' (trade names) are used. Further, the saponification degree of polyvinyl alcohol is 80 mol% or more, preferably 85 mol% or more (the saponification degree is measured according to JIS K6726-1977). Alternatively, it may be coated with a modified polyvinyl alcohol containing a structural unit represented by the following general formula (2). General formula (2) (In the formula, R _2-1 and R _2-2 represent an alkyl group or an aryl group having 1 to 6 carbon atoms.) (In the formula, X ₂ is a halogen atom, R _2-1 and R _2-2 are an alkyl group or an aryl group having 1 to 6 carbon atoms.) [In the formula, _Y2 is a group selected from OM, OH, _OR2 , X (M is an alkali metal, _R2 is an alkyl group having 1 to 6 carbon atoms, and X is a halogen atom), _R2-3 ,
_R2-4 represents an alkyl group or an aryl group having 1 to 6 carbon atoms] A block polymer of polysiloxane and a polyvinyl ester polymer reacted with polysiloxane are saponified. The polysiloxane will be specifically shown below.
In addition, in the formula, Me is a methyl group, Et is an ethyl group, and
Ph represents a phenyl group. The reaction scheme of the block copolymer of the present invention is

[Formula] Polyvinyl acetate polymerization with groups body and both ends

An example of the production of a block copolymer by the reaction of polydimethylsiloxane with [Formula] group is shown schematically by the following reaction formula (2-):
(2-) and (2-). The degree of polymerization of the polyvinyl ester polymer and polysiloxane is appropriately selected depending on the composition and performance of the target block copolymer, but the degree of polymerization of the polyvinyl ester polymer is 50 to 10,000, preferably 100 to 100.
2000, polysiloxane 5-5000, preferably 10
~1000 is preferable from the viewpoint of the balance between the reactivity of the terminal group and the performance of the copolymer. The thus obtained block copolymer of polyvinyl ester polymer and polysiloxane is saponified by a conventional method to partially or highly saponify the polyvinyl ester polymer to produce a polyvinyl alcohol polymer. By doing so, a block copolymer of a polyvinyl alcohol polymer and a polysiloxane can be obtained. The saponification reaction can be carried out by known methods such as the so-called alcoholysis method in which the reaction is carried out in the presence of alcohol using a saponification catalyst, or the direct saponification method in which an appropriate amount of alkali or acid is directly reacted in an aqueous system. A method of saponification by alcoholysis reaction in the presence of a saponification catalyst is preferred because the polysiloxane decomposes less during saponification. As the saponification catalyst, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, alcoholates such as sodium methylate and potassium methylate, alkaline catalysts such as ammonia, or acidic catalysts such as hydrochloric acid and sulfuric acid can be used. . The degree of modification in the modified polyvinyl alcohol having the structural unit of general formula (2) is suitably 60 mol% or less, but preferably 0.05 mol% to 50 mol%.
It is preferable to set it in the range of mol%. In particular, in the present invention, 0.05 mol% to 10 mol% is suitable. Moreover, the degree of polymerization is 1000 to 90000, preferably 10000 to
It is better to set it to 70000. In addition, the degree of saponification of modified polyvinyl alcohol is
It is preferably 80 mol% or more, preferably 85 mol% or more. Further, it may be coated with a modified polyvinyl alcohol containing a structural unit represented by the following general formula (3). General formula (3) (In the formula, R _3-1 is a hydrogen atom or a methyl group, R _3-2 is a hydrogen atom, a halogen atom, a lower alkyl group, an allyl group, or a lower alkyl group having an allyl group,
(R _3-3 is a lower alkyl group and n3 is an integer of 0 to 2) This represents vinyl acetate and the following general formula (3-)
It is a product obtained by saponifying a copolymer with a comonomer represented by: (In the formula, R _3-1 is a hydrogen atom or a methyl group, R _3-2 is a hydrogen atom, a halogen atom, a lower alkyl group, an allyl group, or a lower alkyl group having an allyl group,
(R _3-3 is a lower alkyl group and n3 is an integer of 0 to 2) The comonomer thereof is specifically shown below. Vinyltriacetoxysilane Vinyltripropionyloxysilane isopropenyltriacetoxysilane Vinylisobutyldiacetoxysilane Vinylmethyldiacetoxysilane Vinyldimethylacetoxysilane vinyl phenyl diacetoxysilane Vinyl monochlorodiacetoxysilane vinyl monohydrodiene diacetoxysilane The degree of modification in the modified polyvinyl alcohol having the structural formula of general formula (3) used in the present invention is suitably 30 mol% or less, but preferably
It is preferably in the range of 0.05 mol% to 20 mol%. In particular, in the present invention, 0.05 mol% to 10 mol% is suitable. Moreover, the degree of polymerization is 100 to 10,000, preferably
It is best to set it between 500 and 2000. In addition, the degree of saponification of modified polyvinyl alcohol is
It is preferably 80 mol% or more, preferably 85 mol% or more. Further, it may be coated with a modified polyvinyl alcohol containing a structural unit represented by the following general formula (4). General formula (4) (In the formula, m4 is 0 to 1, n4 is 0 to 2, R _4-1 is a lower alkyl group, an allyl group, or a lower alkyl group having an allyl group, and R _4-2 is a saturated branched chain having 1 to 40 carbon atoms. or an unbranched alkoxy group, and the alkoxy group may have an oxygen-containing substituent) This is a combination of vinyl acetate and the following general formula (4-)
It is a product obtained by saponifying a copolymer with a comonomer represented by: (In the formula, m4 is 0 to 1, n4 is 0 to 2, R _4-1 is a lower alkyl group, an allyl group, or a lower alkyl group having an allyl group, and R _4-2 is a saturated branched chain having 1 to 40 carbon atoms. or an unbranched alkoxy group, and the alkoxy group may have an oxygen-containing substituent) The comonomer thereof is specifically shown below. Examples of the silicon-containing olefinic unsaturated monomer represented by the above general formula (4-) include vinyltrimethoxysilane, vinylmethyldimethoxysilane, vinyldimethylmethoxysilane, vinyltriethoxysilane, and vinylmethyldiethoxysilane. , vinyldimethylethoxysilane, allyltrimethoxysilane, allylmethyldimethoxysilane, allyldimethylmethoxysilane, allyltriethoxysilane, allyldimethylethoxysilane, vinyltris(β-methoxyethoxy)silane, vinylisobutyldimethoxysilane, vinylethyldimethoxysilane, vinyl methoxydiptoxysilane, vinyldimethoxyptoxysilane,
Vinyltriptoxysilane, vinylmethoxydihexyloxysilane, vinyldimethoxyhexyloxysilane, vinyltrihexyloxysilane, vinylmethoxydioctyloxysilane, vinyldimethoxyoctyloxysilane, vinyltrioctyloxysilane, vinylmethoxydilauryloxysilane, Examples include vinyldimethoxylauryloxysilane, vinylmethoxyoleyloxysilane, vinyltriisopropoxysilane, vinyldimethylisopropoxysilane, and vinyldimethoxyoleyloxysilane. The degree of modification in the modified polyvinyl alcohol having general formula (4) as a structural unit used in the present invention is suitably 30 mol% or less, but preferably
It is preferably in the range of 0.05 mol% to 20 mol%. In particular, in the present invention, 0.05 mol% to 10 mol% is suitable. Moreover, the degree of polymerization is 100 to 10,000, preferably
It is best to set it between 500 and 2000. In addition, the degree of saponification of modified polyvinyl alcohol is
It is preferably 80 mol% or more, preferably 85 mol% or more. Further, it may be coated with a modified polyvinyl alcohol containing a structural unit represented by the following general formula (5). General formula (5) [In the formula, R _5-1 is a hydrogen atom or a methyl group, R _5-2 is a hydrogen atom or a lower alkyl group, and R _5-3 is an alkylene group or chain carbon atoms bonded to each other by an oxygen atom or a nitrogen atom. divalent organic residue,
R _5-4 is a hydrogen atom, a halogen atom, a lower alkyl group, an aryl group or a lower alkyl group having an aryl group, R _5-5 hydroxyl group, a salt of a hydroxyl group represented by the formula OM (M represents an alkali metal or NH ₄ ), an alkoxy group or an acyloxy group (however, an alkoxy group or an acyloxy group is a saturated branched or unbranched alkoxy group or an acyloxy group having 1 to 40 carbon atoms,
may have a substituent containing an oxygen atom or a nitrogen atom), n5 represents an integer of 0 to 2] This represents vinyl acetate and the following general formula (5-)
It is a product obtained by saponifying a copolymer with a comonomer represented by: (In the formula, R _5-1 , R _5-2 , R _5-3 , R _5-4 , R _5-5 and n5
(indicates the above meaning) The copolymerized monomers are specifically shown below. 3-(meth)acrylamide-propyltrimethoxysilane 3-(meth)acrylamide-propyltriethoxysilane 2-(meth)acrylamide-propyltriisopropoxysilane 3-(meth)acrylamide-propyltriisobutyroxysilane 3-(meth)acrylamide-propyltri(β-methoxyethoxy)silane 3-(meth)acrylamido-propyltri(N-methylaminoethoxy)silane 2-(meth)acrylamide-ethyltrimethoxysilane 1-(meth)acrylamide-methyltrimethoxysilane 2-(meth)acrylamido-2-methylpropyltrimethoxysilane 2-(meth)acrylamide-isopropyltrimethoxysilane (Meth)acrylamide-linear or branched alkyltrialkoxysilane such as (R represents a hydrogen atom or a methyl group), N-(2-(meth)acrylamide-ethyl)-
Aminopropyltrimethoxysilane CH ₂ = CR・CONH−CH ₂ CH ₂ NH(CH ₂ ) ₃・Si(OCH ₃ ) ₃ (3-(meth)acrylamidopropyl)-oxypropyltrimethoxysilane CH ₂ =CR・(meth)acrylamide-nitrogen-containing or oxygen-containing alkyltrialkoxysilane such as CONH-( _CH2 ) _3-O- (CH2)3Si( _OCH3 ) _{3 (} R represents a hydrogen atom or a _methyl group), 3 -(meth)acrylamide-propyltriacetoxysilane CH ₂ = CR・CONH−(CH ₂ ) ₃ −Si(OCOCH ₃ ) ₃ 2-(meth)acrylamide-ethyltriacetoxysilane CH ₂ =CR・CONH−(CH ₂ ) ₂ -Si(OCOCH ₃ ) ₃ 4-(meth)acrylamido-butyltriacetoxysilane CH ₂ =CR・CONH(CH ₂ ) ₄ -Si(OCOCH ₃ ) ₃ 3-(meth)acrylamido-propyltripropionyloxysilane _CH2 =CR・CONH( _CH2 ) ₃ -Si( _{OCOCH2CH3 ) 3} 2-(meth)acrylamido-2-methylpropyltriacetoxysilane N-(2-(meth)acrylamido-ethyl)-
(Meth)acrylamide-alkyltriacyloxy such as aminopropyltriacetoxysilane CH ₂ =CR・CONH −CH ₂ CH ₂ NH(CH ₂ ) ₃・Si(OCOCH ₃ ) ₃ (R represents a hydrogen atom or a methyl group) Silane, 3-(meth)acrylamide-propylisobutyldimethoxysilane 2-(meth)acrylamide-ethyldimethylmethoxysilane 3-(meth)acrylamide-propyloctyldiacetoxysilane 1-(meth)acrylamide-methylphenyldiacetoxysilane 3-(meth)acrylamide-propylbenzyldiethoxysilane 2-(meth)acrylamido-2-methylpropyl monochlorodimethoxysilane 2-(meth)acrylamido-2-methylpropylhydrodiene dimethoxysilane (Meth)acrylamido-alkyldi- or monoalkoxy or di- or monoacyloxysilane such as (R represents a hydrogen atom or methyl group), 3-(N-methyl-(meth)acrylamido)propyltrimethoxysilane 2-(N-ethyl-(meth)acrylamide)-
Ethyltriacetoxysilane (R represents a hydrogen atom or a methyl group)
Examples include alkyl-(meth)acrylamido)-alkyltrialkoxy or triacetoxysilane. The degree of modification in the modified polyvinyl alcohol having general formula (5) as a structural unit used in the present invention is suitably 30 mol% or less, but preferably
It is preferably in the range of 0.05 mol% to 20 mol%. In particular, in the present invention, 0.05 mol% to 10 mol% is suitable. Moreover, the degree of polymerization is 100 to 10,000, preferably
It is best to set it between 500 and 2000. In addition, the degree of saponification of modified polyvinyl alcohol is
It is preferably 80% by mole or more, preferably 85% by mole or more. Further, it may have a coating of a polyvinyl alcohol polymer containing a reactive silicon group, which is obtained by hydrolyzing a silyl group represented by the following general formula (6), at the molecular end. General formula (6) [In the formula, R _6-1 is a hydrocarbon group having 1 to 20 carbon atoms,
R _6-2 is an alkoxy group, phenoxy group, alkylphenoxy group, or acyloxy group having 1 to 20 carbon atoms (here, the alkoxy group, phenoxy group, alkylphenoxy group, or acyloxy group is an oxygen-containing substituent). ) a group selected from
l6 is an integer from 1 to 3] This is because when copolymerizable monomers such as vinyl acetate are polymerized, a silylthiol compound represented by the following general formula (6-) is present at the terminal. It was synthesized by synthesizing a polyvinyl acetate polymer having a silyl group and saponifying it. General formula (6-) [In the formula, R _6-1 is a hydrocarbon group having 1 to 20 carbon atoms, more preferably a hydrocarbon group having 1 to 10 carbon atoms, R _6-2
is an alkoxy group having 1 to 20 carbon atoms, a phenoxy group,
A group selected from an alkylphenoxy group or an acyloxy group (wherein the alkoxy group, phenoxy group, alkylphenoxy group, or acyloxy group may have an oxygen-containing substituent), R _6-3
is a hydrocarbon residue having 1 to 10 carbon atoms, and l6 is an integer of 1 to 3.] Specific examples of compounds represented by the general formula (6-) include, for example, 3-(trimethoxysilyl). -propylmercaptan, 3-(triethoxysilyl)-propylmercaptan, 2-(trimethoxysilyl)-ethylmercaptan, 3-(dimethoxy-methylsilyl)-propylmercaptan,
Examples include 3-(monomethoxy-dimethylsilyl)-propyl mercaptan. In addition, the vinyl alcohol polymers used in the present invention include polyvinyl alcohols having various degrees of polymerization and saponification, vinyl esters such as vinyl acetate, and small amounts of other polymerizable monomers. (For example, one or more types of α-olefins such as ethylene, propylene, and isobutylene, alkyl vinyl ethers such as methyl vinyl ether, and vinyl chloride) as well as cyanoethylated polyvinyl Also included are polyvinyl alcohol polymers such as alcohol. The degree of modification in the polyvinyl alcohol polymer having the general formula (6) in the basic structure used in the present invention is as follows:
It is suitable to set it to 40 mol% or less, but it is preferably in the range of 0.05 mol% to 20 mol%. In particular, in the present invention, 0.05 mol% to 10 mol% is suitable. Further, the degree of polymerization is preferably 100 to 10,000, preferably 500 to 2,000. Further, the degree of saponification of the polyvinyl alcohol polymer is preferably 80 mol% or more, preferably 85 mol% or more. Alternatively, the membrane may contain a saponified product of a copolymer obtained by copolymerizing a monomer represented by the following general formula (7) and a vinyl ester. General formula (7) (In the formula, R _7-1 , R _7-2 and R _7-3 are an alkyl group, an aryl group, an alkyl group having an aryl group, an alkoxy group, or a hydroxy group, and R _7-1 , R _7-2
and R _7-3 , at least one of which is a hydroxy group. R _7-4 is 2 containing (-CH ₂ ) _-N7 or (-CH ₂ ) _-N7 and a nitrogen atom, sulfur atom or oxygen atom.
It is a highly valent organic residue. However, n7 is 0 or 1 to 10
) This is a saponified copolymer obtained by copolymerizing vinyl acetate, which is a vinyl ester, and a comonomer represented by general formula (7-). General formula (7-) CH ₂ = CH ₂ −R _7-4 −SiR _7-1 R _7-2 R _7-3 (7-) [In the formula, R _7-1 , R _7-2 and R _{7- 3} is an alkyl group (methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, t-butyl group, n-amyl group, t-amyl group, n-hexyl group) group, n-octyl group, t-octyl group, sec
-octyl group, n-nonyl group, n-decyl group, etc.), aryl group (phenyl group, tolyl group, xylyl group, biphenyl group, naphthyl group, etc.), alkyl group having an aryl group, alkoxy group (methoxy group, ethoxy group, etc.) group, propoxy group, butoxy group, acyloxy group, hexyloxy group, etc.) or a hydroxy group, and at least one of R _7-1 , R _7-2 and R _7-3 is a hydroxy group. R _7-4 is
(-CH ₂ )- _N7 or (-CH ₂ )- _N7 and a divalent organic residue containing nitrogen atom (N), sulfur atom (S) or oxygen atom (O) (-O-(CH ₂ ) _o7 , -S-( _CH2 ) _o7 ,

【formula】

[Formula] -NH - (CH ₂ ) _o7 , etc., where n7 is 0 or an integer from 1 to 10)
It is. ] Below, the vinylsilane compound represented by the above general formula will be specifically shown. vinyltrimethoxysilane, vinylmethyldimethoxysilane, vinyldimethylmethoxysilane,
Vinyltriethoxysilane, vinylmethyldiethoxysilane, vinyldimethylethoxysilane, allyltrimethoxysilane, allylmethyldimethoxysilane, allyldimethylmethoxysilane, allyltriethoxysilane, allyldimethylethoxysilane, vinyltris(β-methoxyethoxy)
Silane, vinylisobutyldimethoxysilane, vinylethyldimethoxysilane, vinylmethoxydibutoxysilane, vinyldimethoxybutoxysilane, vinyltributoxysilane, vinylmethoxydihexyloxysilane, vinyldimethoxyhexyloxysilane, vinyltrihexyloxysilane,
Vinylmethoxydioctyloxysilane, Vinyldimethoxyoctyloxysilane, Vinyltrioctyloxysilane, Vinylmethoxydilauryloxysilane, Vinyldimethoxylauryloxysilane, Vinylmethoxydioleyloxysilane, Vinyltriisopropoxysilane, Vinyldimethylisopropoxysilane , trimethoxysiloxyethylene type, 1-acrylamidomethyltrimethoxysilane type, (phenyldimethylsilyl)methyl methacrylate type, 2-vinylsulfoxide ethyltrimethoxysilane type, 1-vinylsulfidemethyltrimethoxysilane type, etc. Examples include sexually unsaturated monomers. The above formula ~ is the following structural formula. formula In addition, the vinyl alcohol polymers having the general formula (7) as a basic structure used in the present invention include polyvinyl alcohols having various degrees of polymerization and saponification, and vinyl esters represented by vinyl acetate. and a small amount of other polymerizable monomers (e.g., α-olefins such as ethylene, propylene, and isobutylene, alkyl vinyl ethers such as methyl vinyl ether, and one or two types of vinyl chloride), etc. This includes not only saponified products of polyvinyl alcohol, but also modified polyvinyl alcohols such as cyanoethylated polyvinyl alcohol. The degree of modification in the modified polyvinyl alcohol having general formula (7) as its basic structure is suitably 30 mol% or less, but preferably 0.05 mol% to 20 mol%.
It is preferable to set it in the range of mol%. Sometimes, the present invention
0.05 mol% to 10 mol% is suitable. Further, the degree of polymerization is preferably 100 to 10,000, preferably 500 to 2,000. In addition, the degree of saponification of modified polyvinyl alcohol is 80.
The amount is preferably 85 mol or more, preferably 85 mol or more. The silyl group of the silicon-containing modified polyvinyl alcohol used in the present invention is completely or partially hydrolyzed during saponification and is substituted with a hydroxy group,
It is presumed that in the coating film, the structural formulas (7a) to (7c) shown below exist singly or in combination. Next, the modified polyvinyl alcohol used for the alignment control films 14a and 14b of the present invention may be polyvinyl alcohol containing sulfur. Specific examples include the following. First, mention may be made of sulfur-containing modified polyvinyl alcohol obtained by reacting polyvinyl alcohol with alkyl vinyl sulfoxide.
As the alkyl vinyl sulfoxide, alkyl vinyl sulfoxides having 1 to 10 carbon atoms such as methyl vinyl sulfoxide, ethyl vinyl sulfoxide, cyclohexyl vinyl sulfoxide, and benzyl vinyl sulfoxide are preferably used. The degree of modification of the modified sulfur-containing modified polyvinyl alcohol resin used in the present invention is suitably 30 mol% or less, but preferably in the range of 1 mol% to 20 mol%. In particular, in the present invention, 1 mol% to 10 mol% is suitable. Moreover, the degree of polymerization is 100 to 10,000, preferably
It is best to set it between 500 and 2000. Further, it may have a coat of modified polyvinyl alcohol containing a structural unit represented by the following general formula (9). General formula (9) (In the formula, R _9-1 represents an alkyl group having 1 to 10 carbon atoms, an aryl group, or a lower alkyl group having an aryl group.) , the following general formula (9-
) was synthesized by reacting the compounds represented by General formula (9-) (In the formula, R _9-1 represents an alkyl group having 1 to 10 carbon atoms, an aryl group, or a lower alkyl group having an aryl group.) The compounds represented by the general formula (9-) are specifically shown below. , methyl vinyl sulfoxide ethyl vinyl sulfoxide butyl vinyl sulfoxide cyclohexyl vinyl sulfoxide benzyl vinyl sulfoxide Suitable examples include alkyl vinyl sulfoxides having an alkyl group having 1 to 10 carbon atoms, and vinyl sulfoxides having an alicyclic hydrocarbon group and a benzyl group. In addition, the vinyl alcohol polymer pair having the general formula (9) as a basic structure used in the present invention includes polyvinyl alcohol having various degrees of polymerization and saponification, and vinyl esters represented by vinyl acetate. and a small amount of other polymerizable monomers (for example, one or more types of α-olefins such as ethylene, propylene, and isobutylene, alkyl vinyl ethers represented by methyl vinyl ether, and vinyl chloride), etc. This includes not only saponified products of polyvinyl alcohol, but also modified polyvinyl alcohols such as cyanoethylated polyvinyl alcohol. The degree of modification in the modified polyvinyl alcohol having the general formula (9) as a basic structure used in the present invention is suitably 30 mol% or less, but preferably
It is preferably in the range of 0.05 mol% or less to 20 mol%. In particular, in the present invention, 0.05 mol% to 10 mol% is suitable. Further, the degree of polymerization is preferably 100 to 10,000, preferably 500 to 2,000. In addition, the degree of saponification of modified polyvinyl alcohol is
It is preferably 80 mol% or more, preferably 85 mol% or more. Further, it may have a coat of modified polyvinyl alcohol containing a structural unit represented by the following general formula (10). General formula (10) (In the formula, R _10-1 represents an alkyl group having 1 to 10 carbon atoms, an aryl group, or a lower alkyl group having an aryl group.) This is a combination of vinyl acetate and the following general formula (10-)
It is a product obtained by saponifying a copolymer with a comonomer represented by: (In the formula, R _10-1 represents an alkyl group having 1 to 10 carbon atoms, an aryl group, or a lower alkyl group having an aryl group.) The comonomer thereof is specifically shown below. Methyl vinyl sulfoxide ethyl vinyl sulfoxide butyl vinyl sulfoxide cyclohexyl vinyl sulfoxide benzyl vinyl sulfoxide Preferred examples include alkyl vinyl sulfoxides having an alkyl group having 1 to 10 carbon atoms, vinyl sulfoxides having an alicyclic hydrocarbon group and a benzyl group, and the like. The degree of modification in the modified polyvinyl alcohol having the general formula (10) as a basic structure used in the present invention is suitably 30 mol% or less, but preferably
It is preferably in the range of 0.05 mol% to 20 mol%. In particular, in the present invention, 0.05 mol% to 10 mol% is suitable. Moreover, the degree of polymerization is 100 to 10,000, preferably
It is best to set it between 500 and 2000. In addition, the degree of saponification of modified polyvinyl alcohol is
It is preferably 80 mol% or more, preferably 85 mol% or more. Also, a polymer having repeating units represented by the following formula (11), and at least one -SR at the end.
Those having a coating of modified polyvinyl alcohol having a group (in the formula, R is a hydrocarbon group having 1 to 18 carbon atoms or a mono- or polyhydroxy hydrocarbon group, and S is a sulfur atom) may also be used. Formula (11) Specific examples of modified polyvinyl alcohol having repeating units represented by formula (11) are shown below. That is, the following general formula (11−) In which R _11-1 is a hydrocarbon group having 1 to 18 carbon atoms. Specifically, R _11-1 is methyl, ethyl,
n-propyl, i-propyl, n-butyl, i-
Butyl, t-butyl, n-hexyl, n-octyl, i-octyl, n-decyl, n-dodecyl,
Examples include modified polyvinyl alcohols having groups such as t-dodecyl, n-tetradecyl, n-hexadecyl, and n-octadecyl. Specific examples of R _11-1 having a mono- or polyhydroxy hydrocarbon group include modified polyvinyl alcohols in which R _11-1 has hydroxyethyl and 2,3-dihydroxypropyl groups. The degree of modification in the modified polyvinyl alcohol having the basic structure of formula (11) used in the present invention is 30 mol%.
It is suitable to be less than or equal to, preferably 0.05
The content is preferably in the range of mol% to 20 mol%. especially,
In the present invention, 0.05 mol% to 10 mol% is suitable.
Moreover, the degree of polymerization is 10 to 10,000, preferably 10 to 10,000.
It is better to set it to 2000. Furthermore, the degree of polymerization of modified polyvinyl alcohol
10 to 200, and the ratio of weight average degree of polymerization to number average polymerization is preferably in the range of 2.0 to 3.0. In addition, the degree of saponification of modified polyvinyl alcohol is
It is preferably 80 mol% or more, preferably 85 mol% or more. Next, the modified polyvinyl alcohol resin may have a coat of modified polyvinyl alcohol containing a structural unit represented by the following general formula (12). General formula (12) In the formula, R _12-1 and R _12-2 are hydrogen atoms, alkyl groups (methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, t-butyl group, n-amyl group, n-amyl group, -hexyl group, n-octyl group, t-
octyl group, etc.), aryl group (phenyl group, naphthyl group, tolyl group, xylyl group, biphenyl group, etc.), alkyl group having an aryl group, halogen atom (F, Cl, Br, I), cyano group or heterocycle ( Pyran, thiapyran, pyridine, tetrahydropyran, tetrahydrothiapyran, imidazole, 2-methylimidazole, 2-ethylimidazole, pyridazine, pyrimidine, pyrazine, thiazole, oxazole, selenazole, pyrrolidine, thiazine, hydantoin, carbazole,
benzothiazole, benzoxazole, benzimidazole, benzoselenazole, naphthothiazole, naphthoxazole, naphthoimidazole, naphthoselenazole, oxadiazole, thiazazole, triazole, etc.). This is a saponified copolymer of a comonomer represented by the general formula (12-) and vinyl acetate. General formula CH ₂ = CR _12-1 R _12-2 (12-) In the formula, R _12-1 and R _12-2 are the aforementioned R _12-1 and
Synonymous with R _12-2 . Specifically, the compounds represented by the general formula (12-) are shown below: ethylene, propylene, 1,
1-dimethylethylene, butylene, 1,1-diethylethylene, styrene, phenylethylene, chlorethylene, dichloroethylene, bromoethylene, dibromoethylene, ethylene iodide, fluoroethylene, difluoroethylene, acrylonitrile, dicyanoethylene, pyridylethylene , 4-vinyltetrahydropyran, 4-vinyltetrahydrothiapyran, 4-vinylpyran, 1
-vinyl-2-methylimidazole, 1-vinyl-2-ethylimidazole, 4-vinylpyridazine, 4-vinylpyrimidine, 3-vinylpyrazine, 2-vinylthiazole, 3-vinylthiazole, 2-vinyloxazole, 1-vinyl Examples include pyrrolidine, 4-vinylthiazine, 5-vinylhydantoin, and 1-vinylcarbazole. In addition, the vinyl alcohol polymers used in the present invention include polyvinyl alcohols having various degrees of polymerization and saponification, vinyl esters such as vinyl acetate, and small amounts of other polymerizable monomers. (For example, one or more types of α-olefins such as ethylene, propylene, isobutylene, alkyl vinyl ethers such as methyl vinyl ether, vinyl chloride, etc.), as well as cyanoethylated polyvinyl It also includes denatured polyvinyl alcohol such as alcohol. The degree of modification in the modified polyvinyl alcohol having general formula (12) as a structural unit used in the present invention is suitably 50 mol% or less, but preferably
It is preferably in the range of 0.05 mol% to 30 mol%. In particular, in the present invention, 0.05 mol% to 20 mol%, more preferably 0.05 mol% to 10 mol% is suitable.
Moreover, the degree of polymerization is 100 to 10,000, preferably 500 to
It is better to set it to 2000. In addition, the degree of saponification of modified polyvinyl alcohol is
It is preferably 80 mol% or more, preferably 85 mol% or more. Next, it may have a coat of modified polyvinyl alcohol containing a structural unit represented by the following general formula (13). General formula (13) (In the formula, R _13-1 is a hydrogen atom or a methyl group, R _13-2
(represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms) This is a process in which the following general formula (13-
) was synthesized by reacting the compounds represented by General formula (13-) CH ₂ = CR _13-1 CONHCH ₂ OR _13-2 (13-) (In the formula, R _13-1 is a hydrogen atom or a methyl group, R _13-2
(represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms) Specific examples of compounds represented by the general formula (13-) include N-methylolacrylamide, N-methylolmethacrylamide, N-methoxymethyl Acrylamide, N-methoxymethylmethacrylamide, N-ethoxymethylmethacrylamide, N-n-propoxymethylacrylamide, N-isopropoxymethylacrylamide, N-n-ptoxymethylacrylamide, N-isoptoxymethylacrylamide, etc. . Among these, in terms of reactivity etc.
N-methylolmethacrylamide and N-methoxymethylmethacrylamide are particularly preferred. In addition, the vinyl alcohol polymers used in the present invention include polyvinyl alcohols having various degrees of polymerization and saponification, vinyl esters such as vinyl acetate, and small amounts of other polymerizable monomers. (For example, one or more types of α-olefins such as ethylene, propylene, and isobutylene, alkyl vinyl ethers such as methyl vinyl ether, and vinyl chloride) as well as cyanoethylated polyvinyl It also includes denatured polyvinyl alcohol such as alcohol. The degree of modification in the modified polyvinyl alcohol having general formula (13) as a structural unit used in the present invention is suitably 30 mol% or less, but preferably
It is preferably in the range of 0.05 mol% to 20 mol%. In particular, in the present invention, 0.05 mol% to 10 mol% is suitable. Moreover, the degree of polymerization is 100 to 10,000, preferably
It is best to set it between 500 and 2000. In addition, the degree of saponification of modified polyvinyl alcohol is
It is preferably 80 mol% or more, preferably 85 mol% or more. Next, it may have a coat of modified polyvinyl alcohol containing a structural unit represented by the following general formula (14). General formula (14) (In the formula, R _14-1 is a hydrogen atom or a methyl group, R _14-2
represents an alkyl group having 1 to 4 carbon atoms) This represents vinyl acetate and the following general formula (14-)
It is a product obtained by saponifying a copolymer with a comonomer represented by: CH ₂ = CR _14-1 −CONHCH ₂ O−R _14-2 (14−) (wherein, R _14-1 is a hydrogen atom or a methyl group, R _14-2
(represents an alkyl group having 1 to 4 carbon atoms) The copolymerized monomers are specifically shown below.
N-methoxymethylacrylamide, N-methoxymethylmethacrylamide, N-ethoxymethylacrylamide, N-ethoxymethylmethacrylamide, N-n-propoxymethylacrylamide, N-n-propoxymethylmethacrylamide, N-isopropoxymethylacrylamide,
N-isopropoxymethyl methacrylamide, N
-n-ptoxymethylacrylamide, N-n-
Examples include ptoxymethyl methacrylamide, N-isoptoxymethyl acrylamide, N-isoptoxymethyl methacrylamide, N-tert-ptoxymethyl acrylamide, N-tert-ptoxymethyl methacrylamide, and the like. The degree of modification in the modified polyvinyl alcohol having general formula (14) as a structural unit used in the present invention is suitably 30 mol% or less, but preferably
It is preferably in the range of 0.05 mol% to 20 mol%. In particular, in the present invention, 0.05 mol% to 10 mol% is suitable. Moreover, the degree of polymerization is 100 to 10,000, preferably
It is best to set it between 500 and 2000. In addition, the degree of saponification of modified polyvinyl alcohol is
It is preferably 80 mol% or more, preferably 85 mol% or more. Next, it may have a coat of modified polyvinyl alcohol containing a structural unit represented by the following general formula (15). General formula (15) (In the formula, R _15-1 and R _15-2 are hydrogen atoms, alkyl groups,
Aryl group, lower alkyl group having an aryl group, allyl group or alkynyl group, or R _15-2 of R _15-1
(indicates a cyclic saturated hydrocarbon group formed by cyclization) This is a cyclic saturated hydrocarbon group formed by cyclization of the following general formula (15-
) was synthesized by reacting the compounds represented by General formula (15−) (In the formula, R _15-1 and R _15-2 are hydrogen atoms, alkyl groups,
Aryl group, lower alkyl group having an aryl group, allyl group or alkynyl group, or R _15-1
R represents a cyclic saturated hydrocarbon group formed by cyclization with , isobutyraldehyde, valeraldehyde, isovaleraldehyde, pivalaldehyde, capronaldehyde, heptaldehyde, caprylaldehyde, pelargonaldehyde, capricaldehyde, undecylaldehyde, lauric aldehyde, tridecyl aldehyde, myristic aldehyde, pentadecyl aldehyde, palmitaldehyde , margaric aldehyde, stearaldehyde, acrolein, crotonaldehyde, propiolaldehyde, benzaldehyde, o-tolualdehyde, m-tolualdehyde,
p-tolualdehyde, salicylaldehyde, cinnamaldehyde, α-naphthaldehyde, β-naphthaldehyde, p-nitrobenzaldehyde,
m-nitrobenzaldehyde, o-nitrobenzaldehyde, p-chlorobenzaldehyde, m-
Chlorobenzaldehyde, o-chlorobenzaldehyde, 2,4-dichlorobenzaldehyde,
Examples include 2,6 dichlorobenzaldehyde, p-fluorobenzaldehyde, m-fluorobenzaldehyde, o-fluorobenzaldehyde, p-bromobenzaldehyde, m-bromobenzaldehyde, o-bromobenzaldehyde, and cyclohexanone. In addition, the vinyl alcohol polymers used in the present invention include polyvinyl alcohols having various degrees of polymerization and saponification, vinyl esters such as vinyl acetate, and small amounts of other polymerizable monomers. (For example, one or more types of α-olefins such as ethylene, propylene, and isobutylene, alkyl vinyl ethers such as methyl vinyl ether, and vinyl chloride) as well as cyanoethylated polyvinyl It also includes denatured polyvinyl alcohol such as alcohol. The degree of modification in the modified polyvinyl alcohol having general formula (15) as a structural unit used in the present invention is suitably 80 mol% or less, but preferably
The content is preferably in the range of 0.05 mol% to 50 mol%. In particular, in the present invention, 0.05 mol% to 20 mol% is suitable. Moreover, the degree of polymerization is 100 to 10,000, preferably
It is best to set it between 500 and 2000. In addition, the degree of saponification of modified polyvinyl alcohol is
It is preferably 80 mol% or more, preferably 85 mol% or more. Next, the modified polyvinyl alcohol used for the alignment control films 14a and 14b of the present invention may be polyvinyl alcohol containing a structural unit represented by the following general formula (16) containing boron. General formula (16) Specifically, those having a structural unit represented by the following formula (16-) can be mentioned. In the formula, x/x+y (mol%) is 0.01 to 30 (mol%), preferably 1 to 20 (mol%). The degree of modification in the modified boron-containing polyvinyl alcohol resin is suitably 30 mol% or less, but preferably in the range of 1 mol% to 20 mol%. In particular, in the present invention, 1 mol% to 10 mol% is suitable. In addition, its degree of polymerization is 100 to 10000, preferably
It is best to set it between 500 and 2000. In addition, the degree of saponification is 80 mol% or more, preferably 85
It is mol% or more. The alignment control films 14a and 14b are formed using these modified polyvinyl alcohol films, which can also function as an insulating film, and are usually 50 Å to 50 Å thick.
The film is formed with a thickness of about 1 μm, preferably 100 Å to 2000 Å, more preferably 500 Å to 2000 Å. In addition, as a method for forming a film of these modified polyvinyl alcohols, 0.1% to 20% by weight of the modified polyvinyl alcohol resin is added to an appropriate solvent.
Preferably, after dissolving in a proportion of 0.2% to 10% by weight, or the precursor solution is applied by a method such as a spinner coating method, a dip coating method, a screen printing method, a spray coating method, or a roll coating method. After that, a method of curing under predetermined curing conditions (for example, heating) can be used. The solvent used in this case is water, glycol,
Glycerol, piperazine, triethylenediamine, formamide, dimethylformamide and the like can be mentioned. Next, a ferroelectric liquid crystal having molecular alignment forming a plurality of layers perpendicular to the planes of a pair of parallel substrates used in the liquid crystal element of the present invention will be described. FIG. 2 schematically depicts an example of a ferroelectric liquid crystal cell using a helical structure. 21a and 2
1b is In ₂ O ₃ , SnO ₂ or ITO (Indium Tin
A substrate (glass plate) coated with a transparent electrode such as SmC ^* (chiral smectic C), in which multiple liquid crystal molecular layers 22 are oriented perpendicularly to the glass substrate surface. ) liquid crystal is enclosed. A thick line 23 represents a liquid crystal molecule, and this liquid crystal molecule 23 has a dipole moment (P⊥) 24 in a direction perpendicular to the molecule.
have. In this case, the tilt angle in the chiral smectic phase of the helical structure is expressed as 1/2 of the angle that forms the apex angle of the triangular pyramid. When a voltage higher than a certain threshold is applied between the electrodes on the substrates 21a and 21b, the helical structure of the liquid crystal molecules 23 is unraveled, and the alignment direction of the liquid crystal molecules 23 is changed so that all dipole moments (P⊥) 24 are directed in the direction of the electric field. can be changed. However, the ferroelectric liquid crystal using this helical structure returns to the original helical structure when no electric field is applied, and does not exhibit the bistability described below. In a preferred embodiment of the invention, a ferroelectric liquid crystal element as shown in FIG. 3 can be used which has at least two stable states, particularly a bistable state, in the absence of an electric field. In other words, when the thickness of the liquid crystal cell is made sufficiently thin (for example, 1μ), the helical structure of the liquid crystal molecules unravels even in the absence of an applied electric field and becomes a non-helical structure, as shown in Figure 3. Child moment Pa or Pb is upward 34a or downward 3
4b, and a bistable state is formed. When an electric field Ea or Eb of different polarity above a certain threshold is applied to such a cell as shown in FIG.
4b and the liquid crystal molecules change direction accordingly.
stable state 33a or second stable state 33
Orient in either direction b. 1st and 2nd at this time
1/2 of the angle formed by the stable state corresponds to the tilt angle θ. There are two advantages to using such a ferroelectric liquid crystal as an optical modulation element. First, the response speed is extremely fast, and the second liquid crystal molecule orientation has bistability. To explain the second point using, for example, FIG. 3, when the electric field Ea is applied, the liquid crystal molecules are oriented in the first stable state 33a, but
This state remains stable even when the electric field is turned off. Furthermore, when an electric field Eb in the opposite direction is applied, the liquid crystal molecules are oriented to a second stable state 33b and the orientation of the molecules is changed, but they remain in this state even after the electric field is turned off. Further, as long as the applied electric field Ea does not exceed a certain threshold value, each orientation state is maintained. In order to effectively realize such a fast response speed and the memory effect of bistability, it is preferable for the cell to be as thin as possible, and in general, a thickness of 0.5 μm to 20 μm, particularly 1 μm to 5 μm is suitable. ing. A liquid-phase electro-optical device having a matrix electrode structure using ferroelectric liquid crystals of this kind has been proposed, for example, by Clark and Ragabal in US Pat. No. 4,367,924. Examples of the ferroelectric liquid crystal that can be used in the liquid crystal element of the present invention include p-decyloxybenzylidene-p'-amino-2-methylbutylcinnamate (DOBAMBC), p-hexyloxybenzylidene-p'-amino-2 -Chlorpropylcinnamate (HOBACPC), p-decyloxybenzylidene-
p'-amino-2-methylbutyl-α-cyanocinnamate (DOBAMBCC), p-tetradecyloxybenzylidene-p'-amino-2-methylbutyl-α-cyanocinnamate (TDOBAMBCC),
p-octyloxybenzylidene-p'-amino-
2-Methylbutyl-α-chlorocinnamate (OOBAMBCC), p-octyloxybenzylidene-p′-amino-2-methylbutyl-α-methylcinnamate, 4,4′-azoxycinnamic acid bis(2- methylbutyl) ester,
4-o-(2-methyl)butylresolcylidene-
4'-octylaniline, 4-(2'-methylbutyl)
Phenyl-4'-octyloxybiphenyl-4-
Carboxylate, 4-hexyloxyphenyl-4-(2″-methylbutyl)biphenyl-4′-carboxylate, 4-octyloxyphenyl-
4-(2″-methylbutyl)biphenyl-4′-carboxylate, 4-heptylphenyl-4-
(4″-methylhexyl)biphenyl-4′-carboxylate, 4-(2″-methylbutyl)phenyl-4-(4″-methylhexyl)biphenyl-4′-
Examples include carboxylates, which can be used alone or in combination of two or more, and can also contain other cholesteric liquid crystals or smectic liquid crystals as long as they exhibit ferroelectricity. Further, in the present invention, a chiral smectic phase can be used as the ferroelectric liquid crystal, and specifically,
Chiral smectic C phase (SmC ^* , H phase (SmH ^* ), I phase (SmI ^* ), K phase (SmK ^* ) and G phase (SmG ^* ) can be used. FIG. 6 is a cross-sectional view schematically showing the uniform orientation state of a liquid crystal element when no voltage is applied. FIG. 6 shows the optical response characteristics to a pulse signal at that time. That is, FIG. 4 is a cross-sectional view of the vertical layer 32 formed of a plurality of chiral smectic liquid crystal molecules shown in the normal direction, and 41 in FIG. 42 represents the tip of the liquid crystal molecule 33a or 33b with respect to the vertical layer 32. Accordingly, according to FIG. By adopting a state in which they are oriented substantially parallel to each other, the tilt angle θ can be brought close to the tilt angle to the maximum. This state is called a uniform orientation state. On the other hand, FIG. 5 is similar to FIG. The arrangement state of liquid crystal molecules in the vertical layer 32 is expressed by the method.As can be seen from FIG. Therefore, the substrates 21a and 2
The liquid crystal molecules adjacent to 1b are not parallel to each other, and the liquid crystal molecules in the vertical layer 32 are oriented in a continuous twisted state from the substrate 21a toward 21b. Such an orientation state is called a splay orientation state. When a predetermined voltage is applied, this splay orientation state takes the uniform orientation state shown in FIG. 4, but once the applied voltage is cut off and the memory state is established, the splay orientation state returns to the splay orientation state shown in FIG. 5. It has been found. Therefore, as shown in FIG. 7, in the splay alignment state, under a voltage applied state, the optical property exhibits high transmittance based on the uniform alignment state, but when no voltage is applied, the original splay orientation with a small chilled angle θ is exhibited. This is the reason why the optical characteristics have low transmittance. On the other hand, in the uniform orientation state shown in Figure 4, the above-mentioned splay orientation state is not adopted, so as shown in Figure 6, even in the memory state when the applied voltage is cut off, high transmittance characteristics are maintained when voltage is applied. It can be maintained as is. In other words, in Figure 6, the voltage is 10V and the pulse width is
A transmittance curve 61 is shown when a pulse 62 of 500 μsec is applied, and it can be seen that the transmittance when the pulse is applied is maintained even under a memory state with a voltage of 0V. Figure 7 shows the same voltage of 10V and pulse width.
It shows a transmittance curve 71 when a pulse 72 of 500 μsec is applied. According to the transmittance curve 71, the transmittance is high for pulse application, and this is the cause of flickering during driving. Furthermore, the transmittance drops sharply under the memory state with a voltage of 0V, which is the cause of the darkness on the display screen. In a preferred embodiment of the present invention, pretreatment by application of an alternating current is effective for the ferroelectric liquid crystal to take the uniform alignment state shown in FIG. This alternating current application pretreatment allows the tilt angle θ described above to be increased to an angle that is equal to or approximately the same as the tilt angle in the helical structure. The AC used in this case can be used at a voltage of 20 to 500 V, preferably 30 to 150 V, and a frequency of 10 to 500 Hz, preferably 10 to 200 Hz, and the application time is about several seconds to 10 minutes, and the AC application pretreatment is performed. can be administered. In addition, such AC application pre-processing is performed at a stage before writing is performed on the liquid crystal element in response to, for example, a video signal or an information signal, and preferably reduces the wait time when such a liquid crystal element is incorporated into a device and the device is operated. The above-mentioned alternating current application pretreatment can be performed, or alternatively, the alternating current application pretreatment can be performed even during the manufacture of such a liquid crystal element. Such AC application pre-processing is performed by adjusting the tilt angle θ before application.
The tilt angle can be increased to the same extent as the tilt angle in the helical structure, and the increased tilt angle can be maintained even after the alternating current application is removed. In addition, such alternating current application pretreatment is performed on ferroelectric liquid crystals with large spontaneous polarization (for example, 5 nc/cm ² or more at 25°C, preferably 10 nc/cm ² to 300 nc/cm ² ; nc is a unit indicating nanocoulombs). It is valid for This spontaneous polarization can be measured using a triangular wave application method* using a 100μ cell. *Japanese Journal of Applied Physics
Applied Physics) No. 22(10), pp. 661-663 (1983
K. Miyasato published in
“Direct Methods with
Dry Angler Waves for Measurement Spontanus Polarization
Direct Method with Triangular
Waves for Measuring Spontaneous
Polarization in Ferroelectric Liquid
[Example] The present invention will be explained below with reference to specific examples and comparative examples. However, parts indicate parts by weight. Example 1-1 Two sheets of 0.7 mm thick glass A plate was prepared, and an ITO film was formed on each glass plate.Aqueous solution in which the following silicon-containing polyvinyl alcohol was dissolved at a ratio of 2% by weight was applied to each glass plate with the ITO film at a rotation speed of 2000 rpm. It was applied with a spinner for 15 seconds. After film formation, it was heated and baked at 180°C for about 1 hour. The thickness of the coating film at this time was about 200 Å. Silicon-containing polyvinyl alcohol Degree of polymerization: 1750 Degree of saponification: 98.2 mol% x/x+y mol% 15 mol% This fired film is rubbed with acetate flocked cloth, then washed with isopropyl alcohol solution, and alumina with an average particle size of approximately 1 μm is applied. After scattering the beads on one glass plate, the two glass plates were stacked so that their respective rubbing axes were parallel to each other to create a cell. The cell thickness of this cell was measured using a Bereck phase plate (measurement based on phase difference) and was found to be approximately 1 μm. Inside this cell, there is a “CS-
1011” (product name) under the isotropic phase,
Orientation could be achieved by slowly cooling from the isotropic phase to 60°C at a rate of 0.5°C/h. Subsequent experiments were conducted at 60°C.
I went there. The phase change of "CS-1011" mentioned above was as follows. SmC ^* 56℃ ―――→ ←――― 53℃SmA78℃ ―――→ ←――― 76℃Ch94℃ ――――→ ←――― 90℃Iso (SmA; Smectic A, Ch; Cholesteric phase Iso ; indicating an isotropic phase) When this cell was observed under crossed nicol conditions, monodomains were obtained that formed a chiral smectic C phase with a uniform, defect-free, non-helical structure. Next, apply a frequency of 70V to the liquid crystal cell described above.
A high electric field alternating current of 70 Hz was applied for about 1 minute (alternating current application pretreatment). When we measured the tilt angle θ at this time, we found that
It was 18°. This tilt angle θ is determined by applying a pulsed electric field (10 V, 500 μsec) to the liquid crystal cell, aligning the direction of the liquid crystal molecules to one stable state, and then rotating the liquid crystal cell under crossed Nicols to obtain the lowest amount of transmitted light. Find the position where the dark state occurs, then apply a pulsed electric field (-10V, 500μsec) with the opposite polarity to the previous pulse.
By applying , the liquid crystal cell is transferred to the other stable molecular alignment state to become a bright state, and then measurement can be performed by rotating the liquid crystal cell again and finding the angle at which the darkest state occurs. The positions of these two darkest states correspond to the detection of a stable average molecular axis of the liquid crystal, and the angle between these two states corresponds to the chilled angle 2θ. It was found that the liquid crystal cell of this example maintained a tilt angle of 18° for a period of one week or more. Furthermore, when the liquid crystal element of this example was multiplexed and driven under the following driving conditions, a flicker-free display screen was formed. Driving conditions (1) 1st step; pulse width 500 μsec for all scans,
Pulse width for 10V signal and all signal lines
Apply a signal of -5V for 500μsec at once. (2) Second step: Pulse width as scanning selection signal
Using 500μsec and voltage of 10V, this signal is sequentially applied to the scanning lines, and in synchronization with this scan selection signal, a signal of pulse width of 500μsec and voltage of 5V and a signal of pulse width of 500μsec and voltage of -5V are selectively output. Apply to the line. Examples 1-2 to 1-20 The silicon-containing polyvinyl alcohol resin and resin used when creating the liquid crystal cell of Example 1-1 were replaced with modified polyvinyl alcohol resins listed in Tables 1-1 to 1-3 below. Other than that, a liquid crystal cell was prepared in exactly the same manner as in Example 1-1, and the same AC pretreatment as in Example 1-1 was performed. Tilt angle θ at that time
And the tilt angle θ was measured after being left for one week. These results are shown in Tables 1-1 to 1-3 (in the tables, "PVA" represents polyvinyl alcohol).

【table】

【table】

[Table] Surface screens of each of these liquid crystal cells were formed by multiplexing driving in the same manner as in Example 1-1, but there was no flickering during writing in any of them even one week after the AC application pretreatment. Ta. Examples 2-1 46.5 parts of vinyl acetate, 2.4 parts of dimethylchlorohydrosilane [ _Me2Si (C1)H], 0.27 parts of azobisisobutyronitrile and 50 parts by volume of benzene were placed in a polymerization tube, and the tube was replaced with nitrogen and then sealed. The mixture was polymerized by heating at 60° C. for 6 hours while stirring. After the polymerization was completed, the solution in the polymerization tube was vacuum distilled to remove unreacted vinyl acetate and dimethylchlorohydrosilane with benzene, yielding 10 parts of a polymer. As a result of GPC analysis, the degree of polymerization was 128. This polymer was dissolved in 100 parts by volume of dehydrated and dried benzene, and the terminal sodium silanolate [NaO-(Me ₂・Si-O-)-
₁₈ Na] and 150 parts by volume of dry benzene were added and reacted after stirring at room temperature for 1 hour. Next, 10 parts by volume of trimethylchlorosilane [Me ₃ SiC] was added and further stirred for 1 hour. produced by filtering the reaction mixture
After removing NaCl, the solution was heated to distill off benzene, the remaining polymer was extracted and washed with n-hexane, the polydimethylsiloxane homopolymer was extracted and removed, and then dried to obtain 12 parts of residual polymer. Add 30 parts of methyl alcohol to 50 parts of a 20% solution of the polyvinyl acetate-polydimethylosiloxane block polymer thus obtained in tetrahydrofuran, maintain at 40°C, and add a 20% methanol solution of sodium methylate to this solution. Add 8.3 parts of , 60
After separating the polymer that precipitated after being left to stand, it was neutralized with methanol containing acetic acid, washed well with methanol, and heated to 60°C.
The mixture was dried for 5 hours to obtain 5.3 parts of polyvinyl alcohol modified with polysiloxane represented by the following formula (2-). Degree of polymerization: 12000 Degree of saponification: 97.7 mol% Degree of modification: 14 mol% A liquid crystal element was produced using this modified polyvinyl alcohol as an alignment film. A liquid crystal cell was created in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell in Example 1-1 was replaced with the modified polyvinyl alcohol resin described above. , the same AC application pretreatment as in Example 1-1 was performed. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 2-
Shown in 1. Example 2-2 95 parts of vinyl acetate, 5 parts of diphenylhydrochlorosilane, 0.4 parts of benzoyl peroxide and 50 parts of tetrahydrofuran were placed in a polymerization tank, the atmosphere was replaced with nitrogen, and the mixture was heated at 30°C for 5 hours while stirring under a nitrogen atmosphere. Polymerization was carried out by heating. After a predetermined time, the interior volume of the polymerization tank was vacuum distilled to remove tetrahydrofuran, unreacted vinyl acetate, and diphenylhydrochlorosilane, yielding 18 parts of a polymer. As a result of GPC analysis, the degree of polymerization was 245. After dehydrating and drying 10 parts of this polymer, it was dissolved in 100 parts of tetrahydrofuran, and added to the polydiphenylsiloxane terminal potassium silanolate. 10 parts of a dry tetrahydrofuran solution containing 0.56 parts
Add it dropwise while stirring at 40℃, and add 2 more times after the addition is complete.
Stir at 40° C. for an hour. After the reaction mixture was filtered to separate the formed crystals, the liquid was heated to distill off tetrahydrofuran, yielding 10.5 parts of residual solid polymer. A 5:1 mixed solution of 20% methyl alcohol and methyl acetate of this block copolymer of polyphenylsiloxane and polyvinyl acetate was prepared and heated to 35°C. 0.3 parts by volume of a 1N methanol solution of sodium hydroxide was added to 20 parts of this solution, and the mixture was thoroughly stirred.
After the system gelled solid, it was ground. The powder was neutralized by immersing it in methanol containing acetic acid, and then thoroughly washed with methanol. When the powder was dried, 2.2 parts of polyvinyl alcohol modified with polysiloxane represented by the following formula (2-) was obtained. Degree of polymerization: 44000 Degree of saponification: 89 mol% Degree of modification: 4 mol% Using this modified polyvinyl alcohol as an alignment film, a liquid crystal element was produced in the same manner as in Example 1-1. A voltage was applied to the prepared liquid crystal cell in the same manner as in Example 1-1.
A high electric field alternating current of 70 V and a frequency of 70 Hz was applied for about 1 minute (alternating current application pretreatment). The tilt angle θ at this time was measured. In addition, the tilt angle θ was measured after being left for one week. These results are shown in Table 2-1. Also, there was no flickering when writing. Example 2-3 50 parts of vinyl acetate, 1.5 parts of diethylchlorohydrosilane [(C ₂ H ₅ ) ₂ Si(Cl)H], 2,2'-azobis-
0.2 parts of 2,4-dimethylvaleronitrile was placed in a polymerization tank, the atmosphere was replaced with nitrogen, and the mixture was heated and polymerized at 55° C. for 3 hours with stirring. After the polymerization was completed, unreacted vinyl acetate and diethylchlorohydrosilane were distilled off under vacuum to obtain 12 parts of polymer. It was found that this polymer had a polymerization degree of 405 and had diethylchlorosilane at the end.
This polymer was dissolved in 100 parts of dehydrated toluene.
This polymer solution was mixed with polydimethylsiloxane with sodium silanolate at both ends (degree of polymerization 350).
It was dropped into 200 parts of a toluene solution containing 90 parts. After the dropwise addition was completed, stirring was continued for 2 hours at 30°C, then 5 parts of a toluene solution containing 1 part of trimethylchlorosilane was added, and the mixture was further stirred for 1 hour. The liquid from which the precipitated crystals were separated was evaporated in vacuo, the remaining polymer was washed with petroleum ether, and then the polymer was dried. As a result, 15 parts of polymer were obtained. Prepare a 20% dioxane solution of this polymer,
0.5% of sodium hydroxide at 50 °C in 50 parts of the solution
Add 10 parts of methyl alcohol solution, stir for 30 minutes,
After separating the precipitated polymer, it was thoroughly washed with 5% aqueous ethyl alcohol, further thoroughly washed with methyl alcohol, dried, and 7 parts of the following formula (2-
) Polyvinyl alcohol modified with polysiloxane was obtained. Degree of polymerization: 60,000 Degree of saponification: 98.5 mol% Degree of modification: 45 mol% A liquid crystal element was produced in the same manner as in Example 1 using this modified polyvinyl alcohol as an alignment film. A voltage of 70V was applied to the fabricated liquid crystal cell as in Example 1.
A high electric field AC with a frequency of 70 Hz was applied for about 1 minute (AC application pretreatment). The tilt angle θ at this time was measured. In addition, the tilt angle θ was measured after being left for one week. These results are shown in Table 2-1. Also, there was no flickering when writing.

[Table] Example 3-1 2800 parts of vinyl acetate and 400 parts of methanol in the reaction tank
After charging 63 parts of vinyltriacetoxysilane and purging the system with nitrogen, the system was heated to 60°C. In this system, 2,2'-azobisisobutyronitrile
Polymerization was started by adding 300 parts of a methanol solution containing 7.84 parts. During a reaction time of 4 hours, 355 parts of a methanol solution containing 177 parts of vinyltriacetoxysilane was added dropwise. After expelling unreacted vinyl acetate monomer by introducing methanol vapor, a 35% methanol solution of the copolymer was obtained. While stirring 300 parts of this methanol solution at 40°C, 16 parts of a methanol solution containing 1.6 parts of NaOH was added thereto to perform a saponification reaction. The copolymer produced by this reaction was crushed and washed to obtain polyvinyl alcohol modified with a copolymer unit represented by the following formula (3-) in the form of a white polymer powder. Degree of polymerization: 1250 Degree of saponification: 99.2 mol% Degree of modification: 5 mol% A liquid crystal element was produced using this modified polyvinyl alcohol as an alignment film. A liquid crystal cell was created in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell in Example 1-1 was replaced with the modified polyvinyl alcohol resin described above. , the same AC application pretreatment as in Example 1-1 was performed. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 3-
Shown in 1.

[Table] Examples 3-2 to 3-5 The comonomer vinyltriacetoxysilane used when synthesizing the modified polyvinyl alcohol of Example 3-1 was replaced with the vinyl acyloxysilane listed in Table 3-2. Modified polyvinyl alcohol was synthesized in exactly the same manner as in Example 3-1 except for the following changes.
A liquid crystal cell was prepared and subjected to the same AC application pretreatment as in Example 3-1. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 3-2 (in the table, "PVA" represents polyvinyl alcohol).

[Table] Display images were formed using the same multiplexing drive as in Example 3-1 for each of these liquid crystal cells, but no flicker occurred during writing even one week after the AC application pretreatment. Nakatsuta. Example 4-1 1400 parts of vinyl acetate and 1000 parts of methanol in a reaction tank
After charging 48.5 parts of vinyltriethoxysilane and purging the system with nitrogen, the system was heated to 60°C. In this system, 2,2'-azobisisobutyronitrile
Polymerization was started by adding 1142 parts of a methanol solution containing 42 parts. vinyl ethoxysilane during the reaction time, 5 hours.
101 parts of a methanol solution containing 10.1 parts was added dropwise.
After expelling unreacted vinyl acetate monomer by introducing methanol vapor, a 50% methanol solution of the copolymer was obtained. 40 parts of this methanol solution
While stirring at °C, 7 parts of a methanol solution containing 0.7 parts of NaOH was added to carry out a saponification reaction. The copolymer produced by this reaction was crushed and washed to obtain polyvinyl alcohol modified with a copolymer unit represented by the following formula (4-) in the form of a white polymer powder. Degree of polymerization 1500 Degree of saponification 98 mol% Degree of modification 8 mol% Except for replacing the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell of Example 1-1 with the modified polyvinyl alcohol resin described above, A liquid crystal cell was prepared in exactly the same manner as in Example 1-1, and the same AC pretreatment as in Example 1-1 was performed. When the tilt angle θ at this time was measured, it was 18°. In addition, the tilt angle may change over a period of one week or more.
It was found that the temperature was maintained at 18°. Examples 4-2 to 4-6 Examples except that the comonomer vinyltriethoxysilane used when synthesizing the modified polyvinyl alcohol of Example 4-1 was replaced with the vinyl silane listed in Table 4-1. Modified polyvinyl alcohol was synthesized in exactly the same manner as in Example 4-1 to prepare a liquid crystal cell, and the same pretreatment for application of alternating current as in Example 1-1 was performed. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 4-1 (in the table, "PVA" represents polyvinyl alcohol).

[Table] A display screen was formed from each of these liquid crystal cells by multiplexing driving in the same manner as in Example 4-1, but there was no flickering during writing in any of them even one week after the AC application pretreatment. Ta. Example 5-1 2700 parts of vinyl acetate and 600 parts of methanol in the reaction tank
After adding 2.7 parts of 3-acrylamide-propyltrimethoxysilane and purging the system with nitrogen,
heated to ℃. In this system, 2,2'-azobisisobutyronitrile
200 parts of a methanol solution containing 1.89 parts was added to initiate polymerization. Reaction time: 3-acrylamide during 3 hours
74.6 parts of a methanol solution containing 18.7 parts of propyltrimethoxysilane was added dropwise. After expelling unreacted vinyl acetate monomer by introducing methanol vapor, a 35% methanol solution of the copolymer was obtained. While stirring 100 parts of this methanol solution at 40°C,
A 4 mol% NaOH/methanol solution was added to this to perform a saponification reaction. The copolymer produced by this reaction was crushed and washed to obtain polyvinyl alcohol modified with a copolymer unit represented by the following formula (5-) in the form of a white polymer powder. Degree of polymerization: 1200 Degree of saponification: 99.0 mol% Degree of modification: 0.5 mol% A liquid crystal element was produced using this modified polyvinyl alcohol as an alignment film. A liquid crystal cell was created in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell in Example 1-1 was replaced with the modified polyvinyl alcohol resin described above. , the same AC application pretreatment as in Example 1-1 was performed. When the tilt angle θ at this time was measured, it was 18°. In addition, the tilt angle may change over a period of one week or more.
It was found that the temperature was maintained at 18°. Examples 5-2 to 5-6 The comonomer 3-acrylamide-propyltrimethoxysilane used when synthesizing the modified polyvinyl alcohol of Example 5-1 was replaced with acrylamide silane listed in Table 5-1. Other than that, modified polyvinyl alcohol was synthesized in exactly the same manner as in Example 5-1 to create a liquid crystal cell.
The same AC application pretreatment as in -1 was performed. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 5-1 (in the table, "PVA" represents polyvinyl alcohol).

[Table] Triisopropoxysilane
A display screen was formed from each of these liquid crystal cells by multiplexing drive similar to that in Example 5-1, but none of them exhibited flickering during writing even one week after the AC application pretreatment. Example 6-1 2400 parts of vinyl acetate and 500 parts of methanol were placed in a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, reflux condenser, and thiol compound addition device, and the system was replaced with nitrogen while stirring. After that, check the internal temperature
The temperature was raised to 60℃. To this system, 0.17 parts of 3-(trimethoxysilyl)propyl mercaptan was added (referred to as the initial addition of thiol), and further 0.87 parts of 2,2'-azobisisobutyronitrile was added to initiate polymerization. . Over 3 hours after the start of polymerization, 80 parts of a methanol solution containing 1.8 parts of 3-(trimethoxysilyl)propyl mercaptan (referred to as post-addition of thiol) was added continuously. After continuing the polymerization for 3 hours, the polymerization was stopped. After expelling unreacted vinyl acetate monomer by introducing methanol vapor, a 40% methanol solution of polyvinyl acetate having silyl groups at the ends was obtained.
While stirring the methanol solution of this polymer at 40° C., a methanol solution containing 5 mol % of sodium hydroxide dissolved in vinyl acetate units was added thereto to carry out a saponification reaction. The obtained saponified product was pulverized, thoroughly washed with methanol, and then dried to obtain a polyvinyl alcohol-based polymer containing a silicon group having at least one hydroxyl group at its terminal. Degree of polymerization: 1080 Degree of saponification: 99.7 mol% A liquid crystal element was produced using this polyvinyl alcohol polymer as an alignment film. A liquid crystal cell was created in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell in Example 1-1 was replaced with the modified polyvinyl alcohol resin described above. , the same AC application pretreatment as in Example 1-1 was performed. When the tilt angle θ at this time was measured, it was 19°. In addition, the tilt angle may change over a period of one week or more.
It was found that the temperature remained at 19°. Examples 6-2 to 6-5 3 of the silylthiol compounds used when synthesizing the polyvinyl alcohol polymer of Example 6-1
A liquid crystal cell was prepared by synthesizing a polyvinyl alcohol polymer in exactly the same manner as in Example 6-1, except that -(trimethoxysilyl)propyl mercaptan was replaced with the silylthiol compound listed in Table 6-1. , the same AC application pretreatment as in Example 6-1 was performed. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 6-1 (“PVA” in the table
represents polyvinyl alcohol).

[Table] Pill mercaptan

A display screen was formed from each of these liquid crystal cells by multiplexing drive similar to that in Example 6-1, but none of them exhibited flickering during writing even one week after the AC application pretreatment. Example 7-1 1400 parts of vinyl acetate and 100 parts of methanol in a reaction tank
1 part and 12 parts of vinyltrimethoxysilane were charged, the atmosphere in the system was purged with nitrogen, and then heated to 60°C. To this system, 1142 parts of a methanol solution containing 42 parts of 2,2'-azobisisobutyronitrile was added to initiate polymerization. During a reaction time of 5 hours, 101 parts of a methanol solution containing 2.5 parts of vinyltrimethoxysilane was leaked.
After expelling unreacted vinyl acetate monomer by introducing methanol vapor, a 50% methanol solution of the copolymer was obtained. While stirring 100 parts of this methanol at 40°C, 7 parts of a methanol solution containing 0.7 parts of NaOH was added thereto to carry out a saponification reaction. This copolymer was crushed and washed to obtain modified polyvinyl alcohol having a moiety represented by formula (7-) in the form of a white powder. Degree of polymerization: 1500 Degree of saponification: 99 mol% Degree of modification: 2 mol% A liquid crystal element was produced using this modified polyvinyl alcohol as an alignment film. A liquid crystal cell was created in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell in Example 1-1 was replaced with the modified polyvinyl alcohol resin described above. However, the same pretreatment for application of alternating current as in Example 1-1 was performed. When the tilt angle θ at this time was measured, it was 18°. It was also found that the tilt angle was maintained at 18° for a period of one week or more. Examples 7-2 to 7-9 Example 7 except that the comonomer vinyltrimethoxysilane used when synthesizing the modified polyvinyl alcohol of Example 1-1 was replaced with the vinyl silane listed in Table 7-1. Modified polyvinyl alcohol was synthesized in exactly the same manner as in Example 7-1 to prepare a liquid crystal cell, and the same pretreatment with alternating current application as in Example 7-1 was performed. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 7-1 (in the table, "PVA" represents polyvinyl alcohol).

[Table] Toxysilane A display screen was formed from each of these liquid crystal cells by the same multiplexing drive as in Example 7-1, but even after one week of AC application pretreatment, no flicker occurred during writing. Nakatsuta. Example 8-1 A liquid crystal cell was produced in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol used to create the liquid crystal cell in Example 1-1 was replaced with the sulfur-containing polyvinyl alcohol shown below. make,
The same AC application pretreatment as in Example 1-1 was performed. When we measured the tilt angle θ at that time and the tilt angle θ after leaving it for one week, it was 17.5° and 14.5°, respectively.
It was hot. In addition, when the liquid crystal cell after being left for one week was subjected to multiplexing driving in the same manner as in Example 1-1, the screen did not flicker so much. Sulfur-containing polyvinyl alcohol Polyvinyl alcohol with a degree of polymerization = 1750 and a degree of saponification = 98.2 mol% and methyl vinyl sulfoxide.
It was obtained by reaction in a 10% aqueous sodium hydroxide solution. The degree of denaturation of this modified polyvinyl alcohol is
It was 14.3 mol%. Example 9-1 845 parts of a 5.2% aqueous solution of polyvinyl alcohol (degree of polymerization 1500, degree of saponification 98.2 mol%) was placed in a reaction vessel equipped with a stirrer and a thermometer, and the temperature was raised to 60°C while stirring. After adding 400 parts of a 10% aqueous sodium hydroxide solution and further adding 90 parts of methyl vinyl sulfoxide, the mixture was reacted at 60° C. for 5 hours with stirring. After cooling the reaction container from the outside and cooling the reaction solution to 25° C., the reaction solution was poured into a large amount of methanol, and the precipitated modified polymer was separated. The obtained polymer was further thoroughly washed with methanol to remove the catalyst and unreacted methyl vinyl sulfoxide, and then dried at 70°C for 5 hours to obtain 55 parts of the moiety represented by the following formula (9-). Polyvinyl alcohol modified with was obtained. Degree of polymerization: 1500 Degree of saponification: 98.2 mol% Degree of modification: 14.3 mol% A liquid crystal element was produced using this modified polyvinyl alcohol as an alignment film. A liquid crystal cell was created in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell in Example 1-1 was replaced with the modified polyvinyl alcohol resin described above. , the same AC application pretreatment as in Example 1-1 was performed. When the tilt angle θ at this time was measured, it was 20°. In addition, the tilt angle may change over a period of one week or more.
It was found to maintain 20°. Examples 9-2 to 9-5 Example 9- except that the methyl vinyl sulfide used as the modification reagent used when synthesizing the modified polyvinyl alcohol of Example 9-1 was replaced with the vinyl sulfide listed in Table 9-1. A liquid crystal cell was prepared by synthesizing modified polyvinyl alcohol in exactly the same manner as in Example 9-1, and the same pretreatment for applying alternating current as in Example 9-1 was performed. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 9-1 (in the table, "PVA" represents polyvinyl alcohol).

[Table] A display screen was formed from each of these liquid crystal cells by multiplexing driving in the same manner as in Example 9-1, but there was no flickering during writing in any of them even one week after the AC application pretreatment. Ta. Example 10-1 500 parts of vinyl acetate and 120 parts of methanol in a reaction tank
After charging 100 parts of methyl vinyl sulfoxide and purging the system with nitrogen, the system was heated to 60°C. In this system, 2,2'-azobisisobutyronitrile
100 parts of a methanol solution containing 0.2 parts was added to initiate polymerization. During a reaction time of 5 hours, 400 parts of a methanol solution containing 300 parts of ethyl vinyl sulfoxide was added dropwise. After expelling unreacted vinyl acetate and methyl vinyl sulfoxide monomers by introducing methanol vapor, a 50% methanol solution of the copolymer was obtained. While stirring 300 parts of this methanol solution at 40°C, 16 parts of a methanol solution containing 1.6 parts of NaOH were added thereto to perform a saponification reaction. The copolymer produced by this reaction was crushed and washed to obtain a white polymer powder. The above modified polyvinyl alcohol was purified by washing under reflux with methyl acetate (containing a small amount of water) and Soxhlet washing with methanol.
This was carried out for 48 hours to obtain polyvinyl alcohol modified with a copolymer unit represented by the following formula (10-). Degree of polymerization: 1800 Degree of saponification: 96 mol% Degree of modification: 4 mol% A liquid phase element was produced using this modified polyvinyl alcohol as an alignment film. A liquid crystal cell was created in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell in Example 1-1 was replaced with the modified polyvinyl alcohol resin described above. , the same AC application pretreatment as in Example 1-1 was performed. When the tilt angle θ at this time was measured, it was 18°. In addition, the tilt angle may change over a period of one week or more.
It was found that the temperature was maintained at 18°. Examples 10-2 to 10-5 Examples except that the comonomer methyl vinyl sulfoxide used when synthesizing the modified polyvinyl alcohol of Example 10-1 was replaced with the vinyl sulfoxide listed in Table 10-1. A liquid crystal cell was prepared by synthesizing modified polyvinyl alcohol in exactly the same manner as in Example 10-1, and was subjected to the same AC application pretreatment as in Example 10-1. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 10-1 (in the table, "PVA" represents polyvinyl alcohol).

[Table] A display screen was formed from each of these liquid crystal cells using the same multiplexing drive as in Example 10-1, but there was no flickering during writing in any of them even one week after the AC application pretreatment. Ta. Example 11-1 960 parts of vinyl acetate and 230 parts of methanol in the reaction tank
and 0.99 parts of n-dodecyl mercaptan.
After replacing the inside of the system with nitrogen, it was heated to 65°C. To this system, 10 parts of a methanol solution containing 0.174 parts of 2,2'-azobisisobutyronitrile was added to initiate polymerization. During a reaction time of 5 hours, 60 parts of a methanol solution containing 15.3 parts of n-dodecylmercaptan was added dropwise. After 5 hours, the container was cooled and the remaining vinyl acetate was expelled from the system together with methanol under reduced pressure.
A 72% methanol solution of was obtained. Take a part of this methanol solution and calculate the PVAc concentration.
50%, [NaOH]/[vinyl acetate] = 0.1 (molar ratio)
A methanol solution of NaOH was added and saponified at 40°C to obtain modified polyvinyl alcohol with a degree of saponification of 99.2%. The above modified polyvinyl alcohol was purified by washing under reflux with methyl acetate (containing a small amount of water) and Soxhlet washing with methanol.
This was carried out for 48 hours to obtain a modified polyvinyl alcohol represented by the following formula (11-). Degree of polymerization: 80 Degree of saponification: 99.2 mol% A liquid crystal element was produced using this modified polyvinyl alcohol as an alignment film. A liquid crystal cell was created in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell in Example 1-1 was replaced with the modified polyvinyl alcohol resin described above. , the same AC application pretreatment as in Example 1-1 was performed. When the tilt angle θ at this time was measured, it was 18°. In addition, the tilt angle may change over a period of one week or more.
It was found that the temperature was maintained at 18°. Examples 11-2 to 11-4 Example 11-1 and Example 11-1 except that the modified polyvinyl alcohol resin used when creating the liquid crystal cell of Example 11-1 was replaced with the modified polyvinyl alcohol listed in Table 11-1. A liquid crystal cell was prepared in exactly the same manner, and the same pretreatment for application of alternating current as in Example 11-1 was performed. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 11-1 (in the table, "PVA" represents polyvinyl alcohol).

[Table] Example 12-1 1400 parts of vinyl acetate and methanol were placed in a reaction tank equipped with a stirrer, thermometer, dropping funnel and reflux condenser.
A mixture of 2,500 parts of 1-vinyl-2-methylimidazole and 1.7 parts of 1-vinyl-2-methylimidazole was placed in a constant temperature bath, and the system was purged with nitrogen while stirring, and then the internal temperature was raised to 60°C. To this system, 21 parts of 2,2'-azobisisobutyronitrile was added as a radical initiator to initiate polymerization. During the polymerization time of 2 hours and 30 minutes, 1-
10 parts of vinyl-2-methylimidazole was added dropwise depending on the solid content concentration in the system. Vinyl acetate monomer remaining in the system was expelled by a conventional method. The copolymer of vinyl acetate and 1-vinyl-2-methylimidazole thus obtained was saponified with caustic soda to form the following formula (12-).
Polyvinyl alcohol modified at the site (unit) shown was obtained. Degree of polymerization: 1900 Degree of saponification: 91 mol% Degree of modification: 0.4 mol% A liquid crystal element was produced using this modified polyvinyl alcohol as an alignment film. A liquid crystal cell was created in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell in Example 1-1 was replaced with the modified polyvinyl alcohol resin described above. However, the same pretreatment for application of alternating current as in Example 1-1 was performed. When the tilt angle θ at this time was measured, it was 19°. In addition, the tilt angle may change over a period of one week or more.
It was found that the temperature remained at 19°. Example 12-2 Add 250 parts of vinyl acetate, 100 parts of tertiary butyl alcohol, and 0.5 part of azobisisobutyronitrile to the autoclave equipped with an electromagnetic vertical stirrer as described in Content 1, and then add about 5 parts of azobisisobutyronitrile to this mixture. Displace and remove dissolved air by blowing nitrogen gas for a minute,
The autoclave lid was closed. Furthermore, nitrogen gas was blown into the autoclave and the replacement was repeated. A similar operation was performed using ethylene gas. Next, heating was started while the stirrer was running, and ethylene was introduced under pressure from a cylinder. Subsequently, the reaction temperature was raised to 65°C, stirring was continued for 3 hours, and the reaction was stopped by cooling the autoclave to room temperature.
Unreacted ethylene was released. After the internal pressure of the autoclave became equal to the external pressure, the lid was opened, and the reaction mixture was taken out and poured into a large amount of water for precipitation. When this product was purified by reprecipitation in an acetone-water system, a copolymer of ethylene and vinyl acetate was obtained. The copolymer of vinyl acetate and ethylene thus obtained was saponified with caustic soda. Degree of polymerization 1500 Degree of saponification 99.2 mol% Degree of modification 17 mol% This modified polyvinyl alcohol was used in Example 12-1
A liquid crystal element was produced by the same operation as above. A voltage was applied to the fabricated liquid crystal cell in the same manner as in Example 12-1.
A high electric field alternating current of 70 volts and a frequency of 70 Hz was applied for about 1 minute (alternating current application pretreatment). Tilt angle θ at this time
When measured, it was 18.5°. In addition, the liquid crystal cell of this example has a tilt angle that remains constant for a period of one week or more.
It was found that the temperature was maintained at 18° or higher, and there was no flickering when writing. Examples 12-3 to 12-5 Cells were created in the same manner as in Example 12-1, except that modified polyvinyl alcohol modified at the sites represented by the following formulas (12-) to (12-) was used. Then, the same AC pretreatment as in Example 12-1 was performed. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 12-1. (“PVA” in the table represents polyvinyl alcohol). formula

【formula】

【formula】

【formula】

[Table] A display screen was formed from each of these liquid crystal cells by multiplexing driving in the same manner as in Example 12-1, but there was no flickering during writing in any of them even one week after the AC application pretreatment. Ta. Example 13-1 10 g of polyvinyl alcohol (degree of polymerization 1700, degree of saponification 99.5 mol%) was added in a 200 ml Erlenmeyer flask.
After dissolving in 90 g of deionized water, 8 ml of 10% sodium hydroxide solution, 15.0 g of N-methylolacrylamide and 0.015 g of hydroquinone monomethyl ether were added and reacted at 65° C. for 3 hours. After the reaction, the reaction mixture was poured into excess methanol to filter out the precipitate, which was then thoroughly washed with methanol, and the catalyst and unreacted substances were removed, and the mixture was dried in a vacuum dryer at 50°C until it reached a constant weight. Weight 11.6g
A polyvinyl alcohol modified at a site represented by the following formula (13-) was obtained. Degree of polymerization: 1700 Degree of saponification: 99.5 mol% Degree of modification: 7.8 mol% A liquid crystal element was produced using this modified polyvinyl alcohol as an alignment film. A liquid crystal cell was created in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell in Example 1-1 was replaced with the modified polyvinyl alcohol resin described above. However, the same pretreatment for application of alternating current as in Example 1-1 was performed. When the tilt angle θ at this time was measured, it was 18°. In addition, the tilt angle may change over a period of one week or more.
It was found that the temperature was maintained at 18°. Examples 13-2 to 13-5 Same as Example 13-1 except that the modifying agent N-methylol acrylamide used when synthesizing the modified polyvinyl alcohol of Example 13-1 was replaced with the acrylamide listed in Table 13-1. A liquid crystal cell was prepared by synthesizing modified polyvinyl alcohol in exactly the same manner as in Example 13-1, and was subjected to the same AC pretreatment as in Example 13-1. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 13-1 (in the table, "PVA" represents polyvinyl alcohol).

[Table]
13-5 N-n-butoxymethylacrylamide 150
0 93.0 12 21.5° 21.0°

A display screen was formed from each of these liquid crystal cells by multiplexing drive similar to that in Example 13-1, and there was no flicker during writing in any of them even one week after the AC application pretreatment. Example 14-1 500 parts of vinyl acetate and 120 parts of methanol in a reaction tank
1 part, 6 parts of N-methoxymethylacrylamide and 0.2 part of 2,2'-azobisisobutyronitrile and heated to 63°C. During a reaction time of 90 minutes, 15 parts of N-methoxymethylacrylide was added dropwise in accordance with the solid content concentration of the polymerization system. This polymerization liquid was charged into a distillation column, and methanol vapor was introduced from the bottom of the column to distill off unreacted vinyl acetate monomer, to obtain a 33% methanol solution of the copolymer. While stirring 300 parts of this methanol solution at 40°C, 12 parts of 1N NaOH methanol solution was added thereto to perform a saponification reaction. After 10 minutes, the entire mixture became a gel. This copolymer was crushed and washed, and a white polymer powder with the following formula (14-
) A polyvinyl alcohol modified with copolymerized units represented by the following formula was obtained. Degree of polymerization: 2200 Degree of saponification: 97.2 mol% Degree of modification: 8.8 mol% A liquid crystal device was produced using this modified polyvinyl alcohol as an alignment film. A liquid crystal cell was created in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell in Example 1-1 was replaced with the modified polyvinyl alcohol resin described above. However, the same pretreatment for application of alternating current as in Example 1-1 was performed. When the tilt angle θ at this time was measured, it was 18°. In addition, the tilt angle may change over a period of one week or more.
It was found that the temperature was maintained at 18°. Examples 14-2 to 14-5 Examples except that the comonomer N-methoxymethylacrylamide used when synthesizing the modified polyvinyl alcohol of Example 14-1 was replaced with acrylamide listed in Table 14-1. A liquid crystal cell was prepared by synthesizing modified polyvinyl alcohol in exactly the same manner as in Example 14-1, and the same pretreatment with alternating current application as in Example 14-1 was performed. The tilt angle θ at this time and the tilt angle θ after being left for one week were measured. These results are shown in Table 14-1 (in the table, "PVA" represents polyvinyl alcohol).

[Table] A display screen was formed from each of these liquid crystal cells by multiplexing driving in the same manner as in Example 14-1, but there was no flickering during writing in any of them even one week after the AC application pretreatment. Ta. Example 15-1 In a 20 ml Erlenmeyer flask, 2.0 g of polyvinyl alcohol (degree of polymerization 1500, degree of saponification 99.5 mol%)
After adding a small amount of hydrochloric acid to 2.0 g of cyclohexanone, the mixture was heated to 45°C with stirring. After 30 minutes, 4 ml of benzene was added and the mixture was reacted for 5 hours. After the reaction, the reaction mixture is poured into a large amount of methanol containing sodium hydroxide necessary for neutralization, the precipitate is filtered, and the resulting polymer is
Furthermore, the catalyst and unreacted substances were thoroughly washed with methanol, and the catalyst and unreacted substances were removed and dried in a vacuum dryer at 50°C until it reached a constant weight.
Polyvinyl alcohol modified at the site shown was obtained. Degree of polymerization: 1500 Degree of saponification: 99.5 mol% Degree of modification: 9 mol% A liquid crystal element was produced using this modified polyvinyl alcohol as an alignment film. A liquid crystal cell was created in exactly the same manner as in Example 1-1, except that the silicon-containing polyvinyl alcohol resin used when creating the liquid crystal cell in Example 1-1 was replaced with the modified polyvinyl alcohol resin described above. However, the same pretreatment for application of alternating current as in Example 1-1 was performed. When the tilt angle θ at this time was measured, it was 18°. In addition, the tilt angle may change over a period of one week or more.
It was found that the temperature was maintained at 18°. Examples 15-2 to 15-5 The denaturing agent cyclohexanone used when synthesizing the modified polyvinyl alcohol of Example 15-1 is shown below.
Modified polyvinyl alcohol was synthesized in exactly the same manner as in Example 15-1 except that the carbonyl compound described in 15-1 was used to prepare a liquid crystal cell, and the same pretreatment for applying AC as in Example 15-1 was performed. I went there. The tilt angle θ at that time and the tilt angle θ after being left for one week were measured. These results are shown in Table 15-1 (in the table, "PVA" represents polyvinyl alcohol).

[Table] A display screen was formed from each of these liquid crystal cells by the same multiplexing drive as in Example 15-1, but there was no flicker during writing in any of them even one week after the AC application pretreatment. Ta. Example 16-1 The silicon-containing polyvinyl alcohol used when creating the liquid crystal cell of Example 1-1 was replaced with the boron-containing polyvinyl alcohol of formula (16) (degree of polymerization =
1750, degree of saponification = 96.5 mol%, x/x+y mol% = 7 mol%), a liquid crystal cell was created in exactly the same manner as in Example 1-1, and the same method as in Example 1-1 was performed. A pretreatment for applying an alternating current was performed. When the tilt angle θ at that time and the tilt angle θ after being left for one week were measured, they were 16.5° and 14°, respectively. In addition, the liquid crystal cell after being left for one week was prepared in Example 1.
I performed multiplexing drive in the same way as the -1, but the screen flickering was not so noticeable. Comparative Example 1 The silane-modified polyvinyl alcohol resin used when creating the liquid crystal cell of Example 1-1 was replaced with polyimide resin (3,3',4,4'-diphenyltetracarboxylic anhydride and p-phenylenediamine). 1:
Example 1-1 except that polyamic acid obtained by dehydration condensation reaction at a molar ratio of 1:1 was replaced with polyimide formed by dehydrating and ring-closing a coating film of 3.5% by weight N-methyl-2-pyrrolidone solution of polyamic acid. A liquid crystal cell was prepared in exactly the same manner and subjected to the same AC application pretreatment as in Example 1-1. When the tilt angle θ of the liquid crystal cell at this time was measured, it was 8°. Moreover, this liquid crystal cell was used in Example 1-
Although the display screen was formed by multiplexing drive similar to No. 1, flickering occurred during writing. Comparative Example 2 Example 1-1 except that the silane-modified polyvinyl alcohol resin used when creating the liquid crystal cell of Example 1-1 was replaced with unmodified polyvinyl alcohol.
A liquid crystal cell was prepared in exactly the same manner as in Example 1-1, and the same AC pretreatment as in Example 1-1 was performed. The tilt angle θ of the liquid crystal cell at this time was measured and found to be 17.5°. Furthermore, when we measured the maintenance time of the 18° tilt angle θ of this liquid crystal cell, we found that
It was found that on the second day, the tilt angle decreased to 15.5°, and after one week, the tilt angle decreased to about 10°. Further, a display screen was formed on the liquid crystal cell after being left for one week by multiplexing driving similar to that in Example 1-1, but flickering occurred during writing. [Effects of the Invention] According to the present invention, it is possible to realize a ferroelectric liquid crystal in a uniform alignment state that can obtain an increased tilt angle, and moreover, it is possible to stably maintain this uniform alignment state for a long period of time. can do.

[Brief explanation of the drawing]

1A and 1B are cross-sectional views showing embodiments of the liquid crystal device of the present invention, FIG. 2 is a perspective view schematically showing a liquid crystal device using a ferroelectric liquid crystal with a spiral structure, and FIG. A perspective view schematically showing a liquid crystal element using a ferroelectric liquid crystal with a non-helical structure, FIG. 4 is a cross-sectional view schematically showing a uniform alignment state, and FIG. 5 is a cross-sectional view schematically showing a splay alignment state. , FIG. 6 is a characteristic diagram showing optical response characteristics in a uniform orientation state, and FIG. 7 is a characteristic diagram showing optical response characteristics in a splay orientation state. 11a...upper substrate, 11b...lower substrate, 12
a, 12b...transparent electrode, 13...ferroelectric liquid crystal, 14a, 14b...alignment control film, 21a, 2
1b...substrate, 22...liquid crystal molecule layer, 23...liquid crystal molecule, 24...dipole moment, 32...vertical layer, 33a...first stable state, 33b...second stable state, 34a ...Upward dipole moment, 34b...Downward dipole moment, ...
Tilt angle in helical structure, θ... Tilt angle in non-helical structure, Ea, Eb... Electric field, 41... Projection of liquid crystal molecules onto vertical layer (C-director), 42...
Tip of liquid crystal molecules relative to vertical layer, 61... Transmittance curve in uniform alignment state, 62, 72...
Pulse, 71...transmittance curve in spray orientation state.

Claims (1)

[Scope of Claims] 1. A liquid crystal element having a pair of parallel substrates and a ferroelectric liquid crystal having a molecular arrangement forming a plurality of layers perpendicular to the planes of the pair of parallel substrates, A liquid crystal element, wherein at least one of the pair of parallel substrates has an alignment control film formed of a modified polyvinyl alcohol resin that preferentially orients the plurality of layers in one direction. . 2. The liquid crystal device according to claim 1, wherein the modified polyvinyl alcohol resin is a silicon-containing modified polyvinyl alcohol resin. 3 The modified polyvinyl alcohol resin is
The liquid crystal element according to claim 2, which is a modified polyvinyl alcohol containing a structural unit represented by any one of the following general formulas (1a), (1b), or (1c). General formula (1a) (In the formula, R _1a-1 and R _1a-2 represent an alkyl group having 1 to 8 carbon atoms) General formula (1b) (In the formula, R _1b represents an alkyl group having 1 to 8 carbon atoms) General formula (1c) (In the formula, X _1c , Y _1c and Z _1c are an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or a hydroxy group, and W _1c is -O-, (-CH ₂ )- _l1 , - O-, (-
_CH2 ) _-n1 or -O( _-CH2 ) _-o1O- . Furthermore, q1 represents 0 or 1, and l1, m1 and n1 represent integers from 1 to 8). 4 The degree of denaturation of the modified polyvinyl alcohol is 30
4. The liquid crystal element according to claim 3, wherein the content is mol % or less. 5 The degree of modification of the modified polyvinyl alcohol is 1
The liquid crystal element according to claim 3, wherein the content is 20 mol %. 6 The degree of modification of the modified polyvinyl alcohol is 1
3. The liquid crystal element according to claim 3, wherein the content is 10 mol %. 7 The degree of polymerization of the modified polyvinyl alcohol is
100 to 10,000, the liquid crystal element according to claim 3. 8 The degree of polymerization of the modified polyvinyl alcohol is
500 to 2000, the liquid crystal element according to claim 3. 9 Claim 2, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol containing a structural unit represented by the following general formula (2).
The liquid crystal element described in . General formula (2) (In the formula, R _2-1 and R _2-2 represent an alkyl group or an aryl group having 1 to 6 carbon atoms.) 10. Claim 9, wherein the modified polyvinyl alcohol contains polysiloxane as a structural unit. liquid crystal element. 11. Claim 9, wherein the modified polyvinyl alcohol is a modified polyvinyl alcohol synthesized by saponifying a block copolymer of a polyvinyl ester polymer and a polysiloxane.
The liquid crystal element described in . 12 The degree of denaturation of the modified polyvinyl alcohol is
The liquid crystal element according to claim 9, wherein the content is 60 mol% or less. 13 The degree of denaturation of the modified polyvinyl alcohol is
The liquid crystal element according to claim 9, wherein the content is 0.05 to 50 mol%. 14 The degree of denaturation of the modified polyvinyl alcohol is
The liquid crystal element according to claim 9, wherein the content is 0.05 to 10 mol%. 15 The degree of polymerization of the modified polyvinyl alcohol is
1000 to 90000. The liquid crystal element according to claim 9. 16 The degree of polymerization of the modified polyvinyl alcohol is
10,000 to 70,000, the liquid crystal element according to claim 9. 17. The liquid crystal device according to claim 2, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol containing a structural unit represented by the following general formula (3). General formula (3) (In the formula, R _3-1 is a hydrogen atom or a methyl group, R _3-2 is a hydrogen atom, a halogen atom, a lower alkyl group, an allyl group, or a lower alkyl group having an allyl group,
_R3-3 represents a lower alkyl group and n3 represents an integer of 0 to 2). 18 The degree of denaturation of the modified polyvinyl alcohol is
18. The liquid crystal element according to claim 17, wherein the content is 30 mol% or less. 19 The degree of denaturation of the modified polyvinyl alcohol is
18. The liquid crystal element according to claim 17, wherein the content is 0.05 to 20 mol%. 20 The degree of denaturation of the modified polyvinyl alcohol is
18. The liquid crystal element according to claim 17, wherein the content is 0.05 to 10 mol%. 21 The degree of polymerization of the modified polyvinyl alcohol is
18. The liquid crystal element according to claim 17, which has a particle size of 100 to 10,000. 22 The degree of polymerization of the modified polyvinyl alcohol is
17. The liquid crystal element according to claim 17, which has a molecular weight of 500 to 2000. 23. The liquid crystal device according to claim 2, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol containing a structural unit represented by the following general formula (4). General formula (4) (In the formula, m4 is 0 to 1, n4 is 0 to 2, R _4-1 is a lower alkyl group, an allyl group, or a lower alkyl group having an allyl group, and R _4-2 is a saturated branched chain having 1 to 40 carbon atoms. or an unbranched alkoxyl group, which may have an oxygen-containing substituent). 24 The degree of denaturation of the modified polyvinyl alcohol is
24. The liquid crystal element according to claim 23, wherein the content is 30 mol% or less. 25 The degree of denaturation of the modified polyvinyl alcohol is
24. The liquid crystal element according to claim 23, wherein the content is 0.05 to 20 mol%. 26 The degree of denaturation of the modified polyvinyl alcohol is
24. The liquid crystal element according to claim 23, wherein the content is 0.05 to 10 mol%. 27 The degree of polymerization of the modified polyvinyl alcohol is
24. The liquid crystal element according to claim 23, which has a particle size of 100 to 10,000. 28 The degree of polymerization of the modified polyvinyl alcohol is
24. The liquid crystal element according to claim 23, which has a particle size of 500 to 2000. 29. The liquid crystal device according to claim 2, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol containing a structural unit represented by the following general formula (5). General formula (5) [In the formula, R _5-1 is a hydrogen atom or a methyl group, R _5-2 is a hydrogen atom or a lower alkyl group, and R _5-3 is an alkylene group or chain carbon atoms bonded to each other by an oxygen atom or a nitrogen atom. divalent organic residue,
R _5-4 is a hydrogen atom, a halogen atom, a lower alkyl group, an aryl group, or a lower alkyl group having an aryl group, R _5-5 is a hydroxyl group, a salt of a hydroxyl group represented by the formula OM (M is an alkali metal or NH ₄ ), alkoxyl group or acyloxyl group (however, an alkoxyl group or acyloxyl group is a saturated branched or unbranched alkoxyl group or acyloxyl group having 1 to 40 carbon atoms, and a substituent containing an oxygen atom or a nitrogen atom is ), n5 represents an integer from 0 to 2]. 30 The degree of denaturation of the modified polyvinyl alcohol is
30. The liquid crystal element according to claim 29, wherein the content is 30 mol% or less. 31 The degree of denaturation of the modified polyvinyl alcohol is
The liquid crystal element according to claim 29, wherein the content is 0.05 to 20 mol%. 32 The degree of denaturation of the modified polyvinyl alcohol is
The liquid crystal element according to claim 29, wherein the content is 0.05 to 10 mol%. 33 The degree of polymerization of the modified polyvinyl alcohol is
29. The liquid crystal element according to claim 29, which has a particle size of 100 to 10,000. 34 The degree of polymerization of the modified polyvinyl alcohol is
29. The liquid crystal element according to claim 29, which has a molecular weight of 500 to 2000. 35. Claim 2, wherein the modified polyvinyl alcohol resin is a polyvinyl alcohol polymer containing at the molecular end a reactive silicon group obtained by hydrolyzing a silyl group represented by the following general formula (6). The liquid crystal element described. General formula (6) [In the formula, R _6-1 is a hydrocarbon group having 1 to 20 carbon atoms,
R _6-2 is an alkoxy group, phenoxy group, alkylphenoxy group, or acyloxy group having 1 to 20 carbon atoms (here, the alkoxy group, phenoxy group, alkylphenoxy group, or acyloxy group is an oxygen-containing substituent). ) a group selected from
l6 is an integer from 1 to 3]. 36 Claim 3, wherein the degree of modification of the modified polyvinyl alcohol polymer is 40 mol% or less
The liquid crystal element according to item 5. 37. The liquid crystal device according to claim 35, wherein the degree of modification of the modified polyvinyl alcohol polymer is 0.05 to 20 mol%. 38 Claim 35, wherein the polyvinyl alcohol polymer has a degree of modification of 0.05 to 10 mol%.
The liquid crystal element described in . 39 Claim 35, wherein the degree of polymerization of the modified polyvinyl alcohol polymer is 100 to 10,000.
The liquid crystal element described in . 40 Claim 35, wherein the modified polyvinyl alcohol polymer has a degree of polymerization of 500 to 2000.
The liquid crystal element described in . 41 A patent in which the modified polyvinyl alcohol resin contains a saponified copolymer obtained by copolymerizing a monomer represented by the following general formula (7) and a vinyl ester A liquid crystal element according to claim 2. General formula (7) (In the formula, R _7-1 , R _7-2 and R _7-3 are an alkyl group, an aryl group, an alkyl group having an aryl group, an alkoxy group, or a hydroxy group, and R _7-1 , R _7-2
and R _7-3 , at least one of which is a hydroxy group. _R7-4 is a divalent organic residue having ( _-CH2 ) _-o7 or ( _-CH2 ) _-o7 and a nitrogen atom, sulfur atom, or oxygen atom. However, n7 is 0 or an integer from 1 to 10). 42 The degree of denaturation of the modified polyvinyl alcohol is
42. The liquid crystal element according to claim 41, wherein the content is 30 mol% or less. 43 The degree of denaturation of the modified polyvinyl alcohol is
42. The liquid crystal element according to claim 41, wherein the content is 0.05 to 20 mol%. 44 The degree of modification of the modified polyvinyl alcohol is
42. The liquid crystal element according to claim 41, wherein the content is 0.05 to 10 mol%. 45 The degree of polymerization of the modified polyvinyl alcohol is
42. The liquid crystal element according to claim 41, which has a particle size of 100 to 10,000. 46 The degree of polymerization of the modified polyvinyl alcohol is
41. The liquid crystal element according to claim 41, which has a molecular weight of 500 to 2000. 47. The liquid crystal device according to claim 1, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol resin containing sulfur. 48. The liquid crystal device according to claim 47, wherein the modified polyvinyl alcohol resin is a sulfur-containing modified polyvinyl alcohol obtained by reacting polyvinyl alcohol with an alkyl vinyl sulfoxide. 49 The degree of denaturation of the modified polyvinyl alcohol is
49. The liquid crystal element according to claim 48, wherein the content is 30 mol% or less. 50. The liquid crystal element according to claim 48, wherein the degree of modification of the modified polyvinyl alcohol is 1 to 20 mol%. 51. The liquid crystal element according to claim 48, wherein the degree of modification of the modified polyvinyl alcohol is 1 to 10 mol%. 52 The degree of polymerization of the modified polyvinyl alcohol is
48. The liquid crystal element according to claim 48, which has a particle size of 100 to 10,000. 53 The degree of polymerization of the modified polyvinyl alcohol is
500 to 2000. The liquid crystal element according to claim 48. 54. The liquid crystal device according to claim 47, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol containing a structural unit represented by the following general formula (9). General formula (9) (In the formula, R _9-1 represents an alkyl group having 1 to 10 carbon atoms, an aryl group, or a lower alkyl group having an aryl group). 55. The liquid crystal device according to claim 54, wherein the modified polyvinyl alcohol is a modified polyvinyl alcohol resin containing sulfoxide. 56 The degree of denaturation of the modified polyvinyl alcohol is
55. The liquid crystal element according to claim 54, wherein the content is 30 mol% or less. 57 The degree of denaturation of the modified polyvinyl alcohol is
55. The liquid crystal element according to claim 54, wherein the content is 0.05 to 20 mol%. 58 The degree of denaturation of the modified polyvinyl alcohol is
55. The liquid crystal element according to claim 54, wherein the content is 0.05 to 10 mol%. 59 The degree of polymerization of the modified polyvinyl alcohol is
55. The liquid crystal element according to claim 54, which has a particle size of 100 to 10,000. 60 The degree of polymerization of the modified polyvinyl alcohol is
54. The liquid crystal element according to claim 54, which has a molecular weight of 500 to 2000. 61. The liquid crystal device according to claim 47, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol containing a structural unit represented by the following general formula (10). General formula (10) (In the formula, R _10-1 represents an alkyl group having 1 to 10 carbon atoms, an aryl group, or a lower alkyl group having an aryl group). 62 The degree of denaturation of the modified polyvinyl alcohol is
62. The liquid crystal element according to claim 61, wherein the content is 30 mol% or less. 63 The degree of denaturation of the modified polyvinyl alcohol is
62. The liquid crystal element according to claim 61, wherein the content is 0.05 to 20 mol%. 64 The degree of denaturation of the modified polyvinyl alcohol is
62. The liquid crystal element according to claim 61, wherein the content is 0.05 to 10 mol%. 65 The degree of polymerization of the modified polyvinyl alcohol is
61. The liquid crystal element according to claim 61, which has a particle size of 100 to 10,000. 66 The degree of polymerization of the modified polyvinyl alcohol is
62. The liquid crystal element according to claim 61, which has a particle size of 500 to 2000. 67 The modified polyvinyl alcohol resin is a polymer having repeating units represented by the following formula (11), and at least one -SR group at the end (in the formula, R is a hydrocarbon group having 1 to 18 carbon atoms). 48. The liquid crystal element according to claim 47, which is a modified polyvinyl alcohol having a mono- or polyhydroxy hydrocarbon group (S represents a sulfur atom). Formula (11) 68 The degree of denaturation of the modified polyvinyl alcohol is
68. The liquid crystal element according to claim 67, wherein the content is 30 mol% or less. 69 The degree of denaturation of the modified polyvinyl alcohol is
68. The liquid crystal element according to claim 67, wherein the content is 0.05 to 20 mol%. 70 The degree of denaturation of the modified polyvinyl alcohol is
68. The liquid crystal element according to claim 67, wherein the content is 0.05 to 10 mol%. 71 The degree of polymerization of the modified polyvinyl alcohol is
67. The liquid crystal element according to claim 67, which has a particle size of 10 to 10,000. 72 The degree of polymerization of the modified polyvinyl alcohol is
10 to 2000. The liquid crystal element according to claim 67. 73 The degree of polymerization of the modified polyvinyl alcohol is
10 to 200, and the ratio of the weight average degree of polymerization to the number average degree of polymerization is 2.0 to 3.0.
The liquid crystal element according to item 7. 74. The liquid crystal device according to claim 1, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol containing a structural unit represented by the following general formula (12). General formula (12) (In the formula, R _12-1 and R _12-2 represent a hydrogen atom, an alkyl group, an aryl group, an alkyl group having an aryl group, a halogen atom, a cyano group, or a residue derived from a heterocycle). 75. The liquid crystal device according to claim 74, wherein the modified polyvinyl alcohol is a modified polyvinyl alcohol resin containing an ethylene moiety. 76. The liquid crystal device according to claim 74, wherein the modified polyvinyl alcohol is a modified polyvinyl alcohol resin containing an ethylene moiety having an alkyl group in a side chain. 77. The liquid crystal device according to claim 74, wherein the modified polyvinyl alcohol is a modified polyvinyl alcohol resin containing a vinyl halide moiety. 78. The liquid crystal device according to claim 74, wherein the modified polyvinyl alcohol is a modified polyvinyl alcohol resin containing an ethylene moiety having a residue derived from a heterocycle. 79 The degree of polymerization of the modified polyvinyl alcohol is
74. The liquid crystal element according to claim 74, which has a particle size of 100 to 10,000. 80 The degree of polymerization of the modified polyvinyl alcohol is
74. The liquid crystal element according to claim 74, which has a particle size of 500 to 2000. 81 The degree of denaturation of the modified polyvinyl alcohol is
75. The liquid crystal element according to claim 74, wherein the content is 50 mol% or less. 82 The degree of denaturation of the modified polyvinyl alcohol is
75. The liquid crystal element according to claim 74, wherein the content is 0.05 to 30 mol%. 83 The degree of denaturation of the modified polyvinyl alcohol is
75. The liquid crystal element according to claim 74, wherein the content is 0.05 to 20 mol%. 84 The degree of denaturation of the modified polyvinyl alcohol is
75. The liquid crystal element according to claim 74, wherein the content is 0.05 to 10 mol%. 85. The liquid crystal device according to claim 1, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol containing a structural unit represented by the following general formula (13). General formula (13) (In the formula, R _13-1 is a hydrogen atom or a methyl group, R _13-2
represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). 86. The liquid crystal device according to claim 85, wherein the modified polyvinyl alcohol is a modified polyvinyl alcohol resin containing an amide. 87 The degree of denaturation of the modified polyvinyl alcohol is
86. The liquid crystal element according to claim 85, wherein the content is 30 mol% or less. 88 The degree of denaturation of the modified polyvinyl alcohol is
86. The liquid crystal element according to claim 85, wherein the content is 0.05 to 20 mol%. 89 The degree of denaturation of the modified polyvinyl alcohol is
86. The liquid crystal element according to claim 85, wherein the content is 0.05 to 10 mol%. 90 The degree of polymerization of the modified polyvinyl alcohol is
100 to 10,000. The liquid crystal element according to claim 85. 91 The degree of polymerization of the modified polyvinyl alcohol is
85. The liquid crystal element according to claim 85, which has a particle size of 500 to 2000. 92. The liquid crystal device according to claim 1, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol containing a structural unit represented by the following general formula (14). General formula (14) (In the formula, R _14-1 is a hydrogen atom or a methyl group, R _14-2
represents an alkyl group having 1 to 4 carbon atoms). 93. The liquid crystal device according to claim 92, wherein the modified polyvinyl alcohol is a modified polyvinyl alcohol resin containing an amide. 94 The degree of denaturation of the modified polyvinyl alcohol is
93. The liquid crystal element according to claim 92, wherein the content is 30 mol% or less. 95 The degree of denaturation of the modified polyvinyl alcohol is
93. The liquid crystal element according to claim 92, wherein the content is 0.05 to 20 mol%. 96 The degree of denaturation of the modified polyvinyl alcohol is
93. The liquid crystal element according to claim 92, wherein the content is 0.05 to 10 mol%. 97 The degree of polymerization of the modified polyvinyl alcohol is
92. The liquid crystal element according to claim 92, which has a particle size of 100 to 10,000. 98 The degree of polymerization of the modified polyvinyl alcohol is
92. The liquid crystal element according to claim 92, which has a molecular weight of 500 to 2000. 99. The liquid crystal device according to claim 1, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol containing a structural unit represented by the following general formula (15). General formula (15) (In the formula, R _15-1 and R _15-2 are hydrogen atoms, alkyl groups,
Aryl group, lower alkyl group having an aryl group, allyl group or alkynyl group, or R _15-1
(represents a cyclic saturated hydrocarbon group formed by cyclization with R _15-2 ). 100 The modified polyvinyl alcohol is 1,3
- The liquid crystal element according to claim 99, which is a modified polyvinyl alcohol resin containing a dioxane ring. 101. The liquid crystal element according to claim 99, wherein the degree of modification of the modified polyvinyl alcohol is 80 mol% or less. 102. The liquid crystal device according to claim 99, wherein the degree of modification of the modified polyvinyl alcohol is 0.05 to 50 mol%. 103. The liquid crystal device according to claim 99, wherein the degree of modification of the modified polyvinyl alcohol is 0.05 to 20 mol%. 104. The liquid crystal device according to claim 99, wherein the modified polyvinyl alcohol has a degree of polymerization of 100 to 10,000. 105. The liquid crystal device according to claim 99, wherein the modified polyvinyl alcohol has a degree of polymerization of 500 to 2,000. 106. The liquid crystal device according to claim 1, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol resin containing boron. 107. The liquid crystal device according to claim 106, wherein the modified polyvinyl alcohol resin is a modified polyvinyl alcohol containing a structural unit represented by the following general formula (16). General formula (16) 108. The liquid crystal device according to claim 107, wherein the degree of modification of the modified polyvinyl alcohol is 30 mol% or less. 109. The liquid crystal device according to claim 107, wherein the degree of modification of the modified polyvinyl alcohol is 1 to 20 mol%. 110. The liquid crystal device according to claim 107, wherein the degree of modification of the modified polyvinyl alcohol is 1 to 10 mol%. 111 The degree of polymerization of the polyvinyl alcohol is
107. The liquid crystal element according to claim 107, which has a molecular weight of 100 to 10,000. 112 The degree of polymerization of the polyvinyl alcohol is
107. The liquid crystal element according to claim 107, which has a particle size of 500 to 2000. 113. The liquid crystal element according to claim 1, wherein the alignment control film has a uniaxial alignment axis. 114 Claim 11, wherein the uniaxial orientation axis is an orientation axis imparted by rubbing treatment.
The liquid crystal element according to item 3. 115. The liquid crystal element according to claim 1, wherein the ferroelectric liquid crystal has a chiral smectic phase. 116. The liquid crystal element according to claim 1, wherein the ferroelectric liquid crystal is a liquid crystal that exhibits at least two stable alignment states in the absence of an electric field.