JP2001323125A - Cholesteric liquid crystal composition, oriented film and multicolor reflective plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cholesteric liquid crystal composition which can form a monodomain oriented film having excellent heat resistance and applicability to a multicolor reflective plate. SOLUTION: The cholesteric liquid crystal composition comprises a crosslinked nematic liquid crystal polymer, a crosslinked cholesteric liquid crystal polymer and a cholesteric phase-providing monomer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cholesteric liquid crystal composition, an alignment film, and a multicolor reflector.
The cholesteric liquid crystal composition of the present invention is subjected to orientation crosslinking treatment to form a monodomain oriented film, which can be used for various optical films and the like. In particular, when preparing an oriented film, a monodomain oriented film in which the content of an optically active group is controlled is useful as a multicolor reflector.

[0002]

2. Description of the Related Art A reflection type liquid crystal display device has a great feature that a backlight is not required as compared with a transmission type liquid crystal display device. Therefore, the display device can be made thinner and lighter. Required power consumption can be reduced. This feature has great utility as a portable device having a liquid crystal display device and a limited power supply capacity, particularly as a display device for a portable notebook personal computer.

In the reflection type display device, it is required to achieve color display in accordance with the transmission type liquid crystal display device. Heretofore, a color display technology using a color filter used in a transmissive liquid crystal display device has also been employed in a reflective display device. However, the reflection type liquid crystal display device using such a color technology has a dark display,
Because of poor visibility, a separate color technology is required.

As a new color technology for such a reflection type liquid crystal display device, a technology utilizing color change (ECB mode) due to birefringence of liquid crystal has been proposed.
However, this colorization technique has a drawback in that the display colors and the number of colors are limited, the multicolor color is poor, and the color purity is poor and the sharpness is poor.

On the other hand, a coloring technique utilizing selective reflection by a low-molecular-weight liquid cholesteric liquid crystal has also been proposed (J. Phys. D: Appl. Phys., V.
ol. 8, 1441; 1975). However, in this color technology, since a liquid crystal is used, the liquid crystal display device has a structure in which the liquid crystal is sandwiched between glass substrates or the like, and is heavy and thick, which is not suitable for a reflection type liquid crystal display device. At the same time, there is a problem that the fluidity of the liquid crystal lowers the fixation of the color sections, and the color characteristics are easily changed by heat.

On the other hand, there has been proposed a film obtained by dissolving a lyotropic liquid crystal polymer in a monomer and polymerizing and fixing the same using actinic rays under temperature control (JP-A-59-83113). However, in this technology, it is necessary to perform color control by temperature, and it is necessary that the liquid crystal polymer has a substrate sandwiching structure at the time of film formation for lyotropic properties. It is difficult to reduce the size of a color section such as a blue region, and it is also difficult to increase the area and mass production.

In order to solve the above problem, Japanese Patent Application Laid-Open No. H10-5
No. 4905 discloses that a photoacid generator is added to a cholesteric liquid crystal polymer having a Schiff base, and the acid generated by irradiation with actinic rays such as ultraviolet rays is used to cut off the Schiff base or the like to obtain a surface of the cholesteric liquid crystal polymer. There has been proposed a multicolor reflector in which the cholesteric pitch in the inside is controlled, and a method of manufacturing the same. This technology is easy to control the display colors and the number of colors, has excellent color purity, and can achieve good visibility display with clear and abundant multi-colors in the reflection type liquid crystal display device. It is possible to manufacture an optical element having excellent fixation properties and in which color characteristics do not easily change at a practical temperature.

However, in order to achieve a sufficient selective reflection color by controlling the cholesteric pitch in the plane of the cholesteric liquid crystal polymer by adjusting the content of the optically active group by the above-mentioned multicoloring treatment step. Although it is essential that the cholesteric liquid crystal polymer has a binding group such as a Schiff base, the cholesteric liquid crystal polymer having a binding group such as a Schiff base has insufficient properties such as thermal stability at the time of heating alignment. However, it is difficult to maintain a constant quality in the multicolor reflector.

[0009]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a cholesteric liquid crystal composition having excellent heat resistance and capable of forming a monodomain oriented film usable for a multicolor reflector or the like. .

[0010]

Means for Solving the Problems The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, have found that the above-mentioned object can be achieved by the cholesteric liquid crystal composition shown below, thereby completing the present invention. Reached.

That is, the present invention provides a compound represented by the general formula (a1):

Embedded image (Wherein R ¹ represents a hydrogen atom or a methyl group, A and D
Each independently represents a cyclic functional group, and X represents -COO-
A group, —OCO— or —O—, E represents a cyano group, an alkyl group, an alkoxy group, a hydroxy group, a chlorine atom or a fluorine atom, and g represents an integer of 2 to 6. And a repeating unit represented by general formula (a2):

Embedded image (Wherein R ¹ represents a hydrogen atom or a methyl group, A and D
Each independently represents a cyclic functional group; X each independently represents a -COO- group, -OCO- group or -O- group;
Represents a crosslinking group, h represents an integer of 2 to 6, and k represents an integer of 0 to 6. A) a cross-linked nematic liquid crystal polymer having a repeating unit represented by formula (a), and a general formula (b1):

Embedded image (Wherein R ¹ represents a hydrogen atom or a methyl group, A and D
Each independently represents a cyclic functional group; X each independently represents a -COO- group, -OCO- group or -O- group;
Is an optically active group that is not modified or deactivated by actinic light,
E represents a cyano group, an alkyl group, an alkoxy group, a hydroxy group, a chlorine atom or a fluorine atom, and r represents an integer of 2 to 6. ) And a general formula (b)
2):

Embedded image (Wherein R ¹ represents a hydrogen atom or a methyl group, A and D
Each independently represents a cyclic functional group; X each independently represents a -COO- group, -OCO- group or -O- group;
Represents a crosslinking group, h represents an integer of 2 to 6, and k represents an integer of 0 to 6. A) a cross-linked cholesteric liquid crystal polymer (b) having a repeating unit represented by:

Embedded image (Wherein R ¹ represents a hydrogen atom or a methyl group, A and D
Each independently represents a cyclic functional group, and X represents -COO-
A group, -OCO- group or -O- group, J represents an optically active group which is modified or deactivated by actinic rays, and w represents an integer of 2 to 6. The present invention relates to a cholesteric liquid crystal composition containing a monomer (c) for imparting cholesteric properties represented by the formula (1).

In the liquid crystal composition of the present invention, in addition to the nematic liquid crystal polymer (a) being cross-linked, the cholesteric liquid crystal polymer (b) is also cross-linked. Since a cross-linked liquid crystal polymer maintaining the above is obtained, heat resistance is improved and thermal stability is good.

The optically active group (L) of the crosslinked cholesteric liquid crystal polymer (b) is stable to actinic rays, while the optically active group (J) of the monomer (c) imparting cholestericity is active. ) Are active and unstable to actinic rays. As described above, the liquid crystal composition of the present invention can control the effective component content of the optically active group relating to the selective reflection property by the optically active group having different stability to actinic rays, and is used for a multicolor reflector and the like. The resulting monodomain oriented film can be formed. The modification or deactivation of the optically active group in the general formulas (b) and (c) means that the optically active group is changed due to cleavage of the bonding group of the optically active group, structural change, isomerization, transition or the like. This means that the state does not effectively contribute to the formation of the helical pitch in the Grandian orientation.

The cholesteric liquid crystal composition of the present invention can be subjected to an alignment treatment by, for example, a method of heating to a temperature equal to or higher than the glass transition temperature and then cooling, and can be converted into a liquid crystal polymer by a crosslinking treatment in a conventional manner. Therefore, according to the conventional cholesteric liquid crystal composition, a large area body of an oriented film having excellent heat resistance can be easily and efficiently produced by the orientation crosslinking treatment at a low temperature. In addition, the liquid crystal composition and the alignment film of the present invention are controlled in the ratio of optically active groups that are active and unstable to actinic rays, so that the stability to acidic impurities in the atmosphere and the solvent and the solution stability are improved. Is also excellent.

In the general formulas (a1), (a2), (b1), (b2) and (c), A and D are not particularly limited as long as they are cyclic functional groups. Considering the orientation of the cholesteric liquid crystal composition, as the cyclic functional group, the following general formula,

Embedded image It is preferably any of the cyclic functional groups represented by

In the general formulas (a2) and (b2), G is not particularly limited as long as it is a cross-linking group, but has a relatively high stability under normal conditions and is relatively easily cleaved by a conventional cross-linking treatment. In that a cross-linking reaction can occur, the following general formula:

Embedded image (Wherein, R ¹ represents a hydrogen atom or a methyl group). Among these crosslinking groups, alicyclic crosslinking groups are preferred because they have no risk of crosslinking at the time of polymerizing the polymer and are easy to synthesize.

L (an optically active group which is not modified or deactivated by actinic rays) in the general formula (b1) is represented by the general formula:

Embedded image (In each formula, t and u are 0 ≦ t ≦ 5, 1 ≦ u ≦ 6, and t
Indicates an integer satisfying + 1 ≦ u. )) Is preferable. Such an optically active group (1) does not contain a linking group such as a Schiff base that is active with respect to actinic rays, is excellent in solution stability and thermal stability at the time of orientation, and has improved heat resistance.

In the general formula (c), J (an optically active group which is modified or deactivated by actinic rays) is represented by the general formula:

Embedded image(In each formula, R^Two Represents a phenyl group, a biphenyl group, 1-naph
A tyl group or a 2-naphthyl group;^Three Is a methyl group,
A phenyl group or a carboxymethyl group; ^Four Hame
It represents a tyl group, a benzyl group or a t-butyl group. * Is not
Shows asymmetric carbon atoms. ) Represents an optically active group (j)
It is preferred that it is a shift. Such an optically active group
(J) makes it possible to easily control the content of the active ingredient in the optically active group.
And the selective reflection characteristics can be improved.

The oriented film of the present invention is obtained by subjecting the cholesteric liquid crystal composition to an orientation treatment and a crosslinking treatment. The orientation film has a monodomain orientation. The oriented film of the present invention can easily produce a large-area film easily and efficiently, and is excellent in heat resistance because it is crosslinked.

Further, in order to apply the alignment film to a multicolor reflector, the cholesteric liquid crystal composition is irradiated with actinic rays controlled for each of a plurality of regions sequentially or simultaneously. Multicolor processing for forming a plurality of regions having different effective contents of optically active groups in the material, and thereafter or simultaneously with the alignment treatment of the cholesteric liquid crystal composition to form a reflection region having a different reflection wavelength for each region. After performing the steps, a crosslinking treatment is further performed. According to such a manufacturing method, a multicolor reflector excellent in heat resistance can be obtained.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The cross-linked nematic liquid crystal polymer (a), cross-linked cholesteric liquid crystal polymer (b), and monomer (c) for imparting cholesteric properties
Can be synthesized by any method.

Cross-linked nematic liquid crystal polymer (a)
Is a copolymer having a repeating unit represented by the general formula (a1) and the general formula (a2). For example, a monomer corresponding to such a repeating unit, that is, a nematic liquid crystal monomer (a1) and a crosslinkable It can be synthesized by copolymerizing the nematic liquid crystal monomer (a2).

Similarly, the crosslinked cholesteric liquid crystal polymer (b) is a copolymer having the repeating units represented by the general formulas (b1) and (b2). It can be synthesized by copolymerizing a corresponding monomer, that is, a monomer (b1) imparting cholestericity and a cross-linkable nematic liquid crystal monomer (b2).

The cross-linking group in the repeating unit represented by the general formula (a2) or (b2) is obtained by copolymerizing the cross-linkable nematic liquid crystal monomers (a2) and (b2) as described above. Can be introduced into the copolymer, or after the monomer capable of introducing the crosslinking group is copolymerized, the monomer can be introduced into the copolymer by a method of introducing the crosslinking group.

The copolymer can be prepared according to a conventional polymerization method of an acrylic monomer such as a radical polymerization method, a cationic polymerization method, or an anion polymerization method. When the radical polymerization method is applied, various polymerization initiators can be used, but the decomposition temperature of azobisisobutyronitrile or benzoyl peroxide is not high, and decomposes at an intermediate temperature that is not low. Are preferably used.

The copolymerization ratio of the crosslinked nematic liquid crystal monomers (a2) and (b2) in the copolymer is preferably about 1 to 30 mol% of the monomers constituting each copolymer. . When the proportion of the crosslinked nematic liquid crystal monomers (a2) and (b2) is reduced, the copolymerization ratio must be 5 in order to cause sufficient crosslinking to obtain high heat resistance.
More preferably, it is at least mol%. On the other hand, when the proportion of the crosslinked nematic liquid crystal monomer (a2) is increased, the orientation as a liquid crystal may be hindered. Therefore, the copolymerization proportion is more preferably 15 mol% or less.

In the liquid crystal composition, the nematic liquid crystal monomer (a1) among the monomers constituting the crosslinked nematic liquid crystal polymer (a) and the monomer among the monomers constituting the crosslinked cholesteric liquid crystal polymer (b) are included. The proportions of the monomer (b1) that imparts cholestericity and the monomer (c) that imparts cholestericity are (a1) :( b1) + (c) = 97: 3 to 5 in molar ratio.
0:50 is preferred, and 95: 5 to 65:35 is more preferred. If the proportion of the monomers (b1) and (c) imparting cholesteric properties is too small, the cholesteric properties of the liquid crystal phase may be poor, while if too large, the liquid crystal properties of the liquid crystal composition may be poor. .

Cross-linked nematic liquid crystal polymer (a),
The molecular weight of the crosslinked cholesteric liquid crystal polymer (b) is preferably about 2,000 to 100,000 based on the weight average molecular weight. When the molecular weight is small, the film-forming property as a non-fluidized layer is poor, so that it is more preferably at least 25,000. In addition, when the molecular weight is large, the orientation as a liquid crystal, in particular, monodomain formation via a rubbing orientation film or the like is poor, and it is difficult to form a uniform orientation state.

An example of the synthesis of the crosslinked nematic liquid crystal polymer (a) represented by the following formula (α) is shown in the following chemical formula (19).

[0030]

Embedded image That is, the nematic liquid crystal monomer (a1)
By esterifying (2-propenoyloxyethoxy) benzoic acid and 4-cyano-4'-hydroxybiphenyl in the presence of dicyclohexylcarbodiimide (where DCC) and dimethylaminopyridine (where DMAP). Obtainable.

The cross-linkable nematic liquid crystal monomer (a2) is, for example, 4- (4'-hydroxyphenyl) benzoic acid in an aqueous sodium hydroxide solution by adding methyl chlorocarbonate and stirring at room temperature to protect the hydroxyl group. Later, 1,
2,5,6-Tetrahydrobenzyl alcohol is reacted to introduce a tetrahydrobenzyl group, and then heated and refluxed in a 25% aqueous ammonia / tetrahydrofuran (THF) mixture (weight ratio: 1/10) to cleave the protective group. And
Further, it can be obtained by adding 4- (2-propenoyloxyethoxy) benzoic acid, followed by esterification in the presence of DCC and DMAP.

Then, these monomers are copolymerized under the azobisisobutyronitrile (AIBN) catalyst to obtain a crosslinked nematic liquid crystal polymer (a) represented by the chemical formula (α). it can. In addition,
1 and m in Chemical formula 19 represent the ratio (mol%) of each repeating unit in the polymer, and satisfy l: m = 99: 1 to 70:30. As described above, the repeating units represented by the general formulas (a1) and (a2) may be block type or random type.

The structure of the above formula (α) is an example of the crosslinked nematic liquid crystal polymer (a) in the present invention, and the crosslinked nematic liquid crystal polymer (a) in the present invention is limited to the above formula (α). Not something.

The nematic liquid crystal monomer (a1)
The synthesis of 4- (2-propenoyloxyethoxy) benzoic acid used for the synthesis of the cross-linked nematic liquid crystal monomer (a2) was carried out using ethylene chlorohydrin and 4-hydroxybenzoic acid as shown in the following Chemical Formula 20. After heating and refluxing in an aqueous alkali solution using potassium chloride as a catalyst to obtain a hydroxycarboxylic acid, it can be obtained by subjecting it to a dehydration reaction with acrylic acid.

[0035]

Embedded image In addition, an example of a synthesis example of the crosslinked cholesteric liquid crystal polymer (b) represented by the following formula (β) is shown in the following formula 21.

[0036]

Embedded image That is, a monomer (b) that imparts cholesteric properties
1) For example, isosorbide is added to p-toluenesulfonic acid and dihydropyran (DHP) in THF and stirred in a greenhouse to protect only one hydroxyl group. Then, this is added to p-cyanobenzoic acid, DCC and DMAP. Esterification reaction, followed by stirring in a hydrochloric acid / THF solution to cleave the protecting group, followed by esterification with 4- (2-propenoyloxyethoxy) benzoic acid in the presence of DCC and DMAP. Can be.

The cross-linked nematic liquid crystal monomer (b2) is the same as the cross-linked nematic liquid crystal monomer (a).
It has the same structure as in 2) and can be obtained by a similar method. These crosslinked nematic liquid crystal monomers (a2) and (b2)
Is a cross-linkable nematic liquid crystal monomer (a2), as long as it does not impair the liquid crystallinity and orientation of the liquid crystal composition.
(B2) may be the same or different, and can be appropriately selected and used without particular limitation. The crosslinked nematic liquid crystal monomer (b2) in Chemical Formula 21 shows the case where the same one as the crosslinked nematic liquid crystal monomer (a2) in Chemical Formula 20 is used.

Then, these monomers are copolymerized under an azobisisobutyronitrile (AIBN) catalyst to obtain a crosslinked cholesteric liquid crystal polymer (b) represented by the chemical formula (β). it can. In addition, x and y in Chemical formula 21 show the ratio of each repeating unit in a polymer, and satisfy x: y = 97: 3 to 50:50, and are represented by a block copolymer for convenience. The repeating units represented by the general formulas (b1) and (b2) may be any of a block type and a random type.

The structure of the formula (β) is an example of the crosslinked cholesteric liquid crystal polymer (b) in the present invention, and the crosslinked cholesteric liquid crystal polymer (b) in the present invention is limited to the formula (β). Not something.

An example of the synthesis of the monomer (c) imparting cholestericity represented by the following formula (γ) is shown in the following formula (22).

[0041]

Embedded image That is, a monomer that imparts cholestericity by esterifying 4- (2-propenoyloxyethoxy) benzoic acid and a phenol having an optically active group at the 4-position via a Schiff base in the presence of a DCC and DMAP catalyst ( γ) can be synthesized.

The phenol having an optically active group at the 4-position via a Schiff base used in the synthesis of the monomer (c) imparting cholestericity is, for example, 4-hydroxybenzaldehyde and (S )-(-)
It can be obtained by azeotropically dehydrating -1-phenylethylamine in toluene.

[0043]

Embedded image Such a structure of the formula (γ) is an example of the cholestericity imparting monomer (c) in the present invention, and the cholestericity imparting monomer (c) in the present invention is not limited to the formula (γ). Absent.

The cholesteric liquid crystal composition of the present invention comprises
The cross-linkable nematic liquid crystal polymer (a), the cross-linked cholesteric liquid crystal polymer (b), and the monomer (c) for imparting cholesteric properties are included. In addition, these liquid crystal polymers and liquid crystal monomers may be used by mixing two or more kinds represented by the above general formula.

If the composition ratio of the crosslinked nematic liquid crystal polymer (a) in the liquid crystal composition is too small, the liquid crystallinity becomes poor and there is a possibility that the liquid crystal composition cannot be aligned.
It is preferable to set the degree. Further, the content of the crosslinked nematic liquid crystal polymer (a) is more preferably 65 to 90% by weight.

The total proportion of the crosslinked cholesteric liquid crystal polymer (b) and the cholesteric monomer (c) in the liquid crystal composition is the balance of the crosslinked nematic liquid crystal polymer (a). The proportion of the monomer (c) for imparting cholesteric property is usually 10% with respect to the monomer (b1) for imparting cholesteric property constituting the crosslinked cholesteric liquid crystal polymer (b).
It is preferably adjusted to about 1000 mol%, more preferably 30 to 300 mol%. If the amount of the monomer (c) imparting cholesteric properties is excessive, an optically active group having poor solution stability and thermal stability will remain after controlling the selective reflection wavelength, which is not preferable. On the other hand, when the amount is too small, there is no particular problem when used for a single color, but when the selectively reflected light is used in multiple colors, the range in which the selective reflection wavelength can be controlled becomes extremely small, and the production of a multicolor reflector Not preferred.

The cholesteric liquid crystal composition of the present invention is obtained by appropriately selecting the liquid crystal polymers (a), (b) and the liquid crystal monomer (c) according to various uses, and synthesizing according to the above method. However, a liquid crystal monomer other than the liquid crystal monomer and a liquid crystal polymer can be contained within a range not to impair the object of the present invention.

The cholesteric liquid crystal composition of the present invention comprises
The orientation film and the cross-linking process are performed to form an oriented film having a monodomain orientation.

The orientation treatment can be performed by an orientation treatment method according to the conventional formation of an optical element. For example, a solution of the cholesteric liquid crystal composition is spread on an alignment-treated surface, dried, and then heat-treated to form an alignment layer.

The solvent used for preparing the liquid crystal composition solution is not particularly limited as long as it can dissolve the liquid crystal polymers (a), (b) and the monomer (c). It can be appropriately selected and used. For example, 1,1,2,2-tetrachloroethane, cyclohexanone, methylene chloride, chloroform,
Tetrahydrofuran and the like. These solvents are used as a single solvent or a mixed solvent.

As the alignment treatment surface, for example, a known surface used for alignment treatment of a low-molecular liquid crystal compound can be used. For example, a thin film made of polyimide, polyvinyl alcohol, or the like is formed on a substrate and rubbed with a rayon cloth or the like, obliquely vapor-deposited silicon oxide, or a stretched film.
The substrate or the like is not particularly limited as long as it can withstand heat treatment for aligning the liquid crystal composition. For example, a glass plate, a polymer sheet, a retardation plate, a polarizing plate, or the like can be appropriately selected and used.

The liquid crystal composition solution is developed by, for example, developing the solution into a thin layer by a method such as a spin coating method, a roll coating method, a flow coating method, a printing method, a dip coating method or a casting film forming method. It can be carried out by a method of drying and removing the solvent.

The heat treatment for aligning the spread layer of the liquid crystal composition can be performed by heating the liquid crystal composition to a temperature range from a glass transition point to a molten state exhibiting an isotropic phase. The cooling conditions for fixing the alignment state are not particularly limited, and generally, the above-described heat treatment is performed for 3 hours.
Since it can be performed at a temperature of 00 ° C. or less, a natural cooling method is generally used.

The developed layer after the orientation treatment is cross-linked to form an oriented cross-linked product. The cross-linking treatment can be performed by one or both of electromagnetic wave irradiation and heating. As the electromagnetic wave, an appropriate one such as an ultraviolet ray or an electron beam can be used. Among them, an electron beam which does not need to add an initiator and has little influence on the initial orientation can be preferably used. The wavelength of the electromagnetic wave and the irradiation amount can be determined as appropriate, but when using ultraviolet light, ultraviolet light having a wavelength longer than 300 nm that does not absorb the liquid crystal composition is preferable, and when using an electron beam,
If the irradiation amount is too large, the liquid crystal polymer will be destroyed. Therefore, depending on the system, it is preferably about 1 to 200 Mrad / cm ² .

The initiator that can be used to cause cross-linking after alignment differs depending on the type of cross-linking. In any case, it is desirable that coloring of the alignment-treated product by the addition of the initiator is of a level that causes no practical problem. First, when crosslinking is performed only by heating, it is necessary to use an initiator having a high decomposition temperature so that crosslinking does not occur during the alignment treatment. Next, referring to the ultraviolet light required for the initiator among the electromagnetic wave crosslinking, only ultraviolet irradiation, or in any case of performing crosslinking by ultraviolet irradiation while heating, those that decompose at the orientation temperature and the heating temperature at the time of crosslinking are not preferred. Any initiator that absorbs the liquid crystal composition and decomposes by ultraviolet rays having a wavelength longer than 300 nm can be used. For example, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 or oligo [2-hydroxy-2-methyl-
1- [4- (1-methylvinyl) phenyl] propanone] and the like are preferably used. Further, the amount of the initiator to be added can be determined as appropriate.

The irradiation of the electromagnetic wave is preferably performed under reduced pressure or oxygen-free condition to avoid the influence of oxygen inhibition. In the case of heat treatment, the liquid crystal composition may be heated at an appropriate temperature within a temperature range higher than the glass transition temperature and lower than the isotropic phase transition temperature.

The oriented film of the present invention may have an appropriate form such as a form having a liquid crystal layer subjected to an alignment treatment on an appropriate substrate or a film form comprising a single layer of the liquid crystal layer subjected to an alignment treatment. . A film composed of a single layer of liquid crystal can be obtained as a peeled product from the alignment-treated surface. Number 8-
An appropriate method such as a method of forming an alignment-treated surface on a glass plate having a surface modified with a silane compound having an alkyl chain of 18 can be applied as needed.

On the other hand, in the case of an oriented film comprising a superimposed material with a substrate, the substrate may be a plastic film, a glass plate, a stretched film such as a polymer sheet or a retardation plate, or an optical film such as a polarizing plate. An appropriate one can be used. As the plastic film,
For example, polymethyl methacrylate or polycarbonate,
Polyvinyl alcohol and polyacrylate, polypropylene and other polyolefins, such as polystyrene,
An optically transparent plastic capable of forming a stretched film can be appropriately selected and used. In addition, as the base material, a material having as small a retardation as possible due to birefringence, such as a glass plate or a triacetyl cellulose film, is particularly desirable.

The thickness of the liquid crystal layer subjected to the alignment crosslinking treatment is as follows:
Although it can be appropriately determined according to the optical characteristics and the like according to the purpose of use, it is generally 100 μm or less in view of flexibility and the like.
0 μm, especially 1 to 30 μm.

The thus-obtained oriented film of the present invention can be used as an optical film exhibiting circular dichroism as a color compensating plate such as a liquid crystal display device, an optical phase plate, a cholesteric film, a notch filter and the like. It is useful for optical film applications.

Further, the cholesteric liquid crystal composition of the present invention is obtained by irradiating a liquid crystal phase spread on a base material layer with active rays controlled in a plurality of regions sequentially or simultaneously, thereby obtaining the cholesteric liquid crystal composition. Forming a plurality of regions having different effective contents of the optically active groups therein, and thereafter or simultaneously with the alignment treatment of the cholesteric liquid crystal composition to form a reflection region having a different reflection wavelength for each region. After that, by further performing a cross-linking treatment, the selective reflection characteristics of the cholesteric liquid crystal were arbitrarily set,
A multicolor reflector excellent in heat resistance can be manufactured.

As the actinic ray, an appropriate ray such as a visible ray, an ultraviolet ray, an electron beam or a gamma ray which can modify or deactivate the optically active group can be used. Among them, ultraviolet rays via a mercury lamp, excimer laser, or the like is preferable from the viewpoint of irradiation energy and the like.

By the irradiation with actinic rays, a binding group such as a Schiff base relating to the optically active group (J) in the monomer (c) imparting cholestericity is cleaved, and a plurality of regions having different effective contents of the optically active group. Is formed, and the selective reflection characteristic of the cholesteric liquid crystal can be set arbitrarily.

The orientation and cross-linking treatments in the production of the multicolor reflector can be performed in the same manner as described above, and the orientation treatment can be carried out simultaneously with the irradiation of actinic rays. In addition, when irradiating with an actinic ray, the liquid crystal phase developed on the base material layer is subjected to an orientation treatment in advance, so that the orientation treatment can be favorably performed after or simultaneously with the irradiation with the actinic ray.

Further, by adding a photoacid generator to the liquid crystal composition to form a non-fluidized bed, the amount of irradiation with actinic rays necessary for cutting the bonding group can be reduced. In this case, cleavage can be performed even at a urethane bond or an -OCOO- bond relating to the optically active group. The compounding amount is generally 25 parts by weight or less, preferably 0.1 to 20 parts by weight, particularly 0.5 to 10 parts by weight, based on 100 parts by weight of the liquid crystal composition, but is not limited thereto.

Suitable photoacid generators include, for example, triazines, aromatic sulfonium salts, aromatic diazonium salts, cyanate esters, aromatic sulfonates, nitrobenzyl esters, aromatic sulfamides and the like. Can be used. Above all, triazines and aromatic sulfonium salts can be preferably used from the viewpoints of the compounding effect and no influence on the liquid crystal alignment.

Specific examples of the above triazines include:
2,4-bis (trichloromethyl) -6- (3 ′, 4 ′
-Dimethoxyphenyl) triazine, 2,4-bis (trichloromethyl) -6- (4'-methoxynaphthyl) triazine, 2,4-bis (trichloromethyl) -6-biperonyltriazine, 2,4-bis ( Trichloromethyl) -6- (4′-methoxy-β-styryl) triazine, 2,4-bis (trichloromethyl) -6- (3′-
Chloro-4′-methoxy-β-styryl) triazine and the like, but are not limited thereto.

Further, specific examples of the aromatic sulfonium salts include those represented by the following chemical formula.

[0069]

Embedded image

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments and the like specifically showing the configuration and effects of the present invention will be described below.

Production Example 1 (Nematic liquid crystal monomer (a
Synthesis of 1))

Embedded image 300 g of potassium hydroxide, 700 ml of ethanol and 3
After dissolving 276 g of 4-hydroxybenzoic acid and a catalytic amount of potassium iodide in the solution, 177 g of ethylene chlorohydrin was gradually added while heating, and the mixture was refluxed for about 15 hours. Was. Ethanol was distilled off from the obtained reaction solution, and then the solution was poured into 2 L of water. The aqueous solution was washed twice with diethyl ether, and hydrochloric acid was added to obtain an acidic solution. Further, the precipitate was separated by filtration and dried, and then recrystallized from ethanol to obtain 298 g of 4- (2-hydroxyethoxy) benzoic acid.

Then, 18.2 g of the above 4- (2-hydroxyethoxy) benzoic acid was added to 300 m of tetrahydrofuran.
19.5 g of vinyl acrylate
And 18.0 g of Lipase PS (manufactured by Amano Pharmaceutical Co., Ltd.) and a small amount of p-methoxyphenol were added, followed by stirring at 40 ° C. for 3 hours. After lipase PS was filtered off from the obtained reaction solution, the filtrate was distilled off under reduced pressure. The resulting solid was recrystallized with a mixed solvent of 2-butanone / hexane = 2/1 (weight ratio) to give 4
-(2-Provenoyloxyethoxy) benzoic acid17.
5 g were obtained.

Next, 9.44 g of 4- (2-propenoyloxyethoxy) benzoic acid and 8.32 ml of trifluoroacetic anhydride were put into 100 ml of methylene chloride, and 4-cyano-4'-hydroxybiphenyl was added with stirring. 7.
8 g was added and reacted at room temperature for 6 hours. 300 ml of methylene chloride was added to the reaction solution, and the mixture was washed with water, a saturated aqueous solution of sodium hydrogencarbonate and saturated saline, and dried over anhydrous sodium sulfate. After filtration and concentration, recrystallization was performed from 150 ml of acetonitrile to obtain 11.7 g of a nematic liquid crystal monomer.
(Chemical purity> 98%).

Production Example 2 (Synthesis of Crosslinked Nematic Liquid Crystalline Monomer (a2))

Embedded image A solution prepared by dissolving 83.86 g of sodium hydroxide and 100 g of 4-hydroxybenzoic acid in 2000 ml of water was cooled on ice, and 91.1 ml of methyl chloroformate was added dropwise thereto with stirring, and then returned to room temperature. Stir for 4 hours. While cooling this solution on a water bath, about 70 ml of concentrated hydrochloric acid was added to the solution to adjust the pH to 2-3, and the precipitated crystals were filtered, washed with water and dried. Further, the product was recrystallized from 1,000 ml of isopropanol to obtain 94.0 g of 4-methoxycarbonyloxybenzoic acid (yield: 66.2%, chemical purity:> 99%).

4-methoxycarbonyloxybenzoic acid 4
0.0 g and 1.50 ml of dimethylformamide were placed in 400 ml of dehydrated chloroform, the system was purged with nitrogen, and 19.34 ml of thionyl chloride was stirred at 40 ° C.
1 was added dropwise. After stirring for 2 hours as it was, the solvent and excess thionyl chloride were distilled off using a trap, and 20.0 ml of dehydrated tetrahydrofuran was added to dissolve the crystals, and then the washing operation of distilling off was repeated twice. To this, 100 ml of dehydrated tetrahydrofuran was added, and further, on an ice bath, 1,2,5,6-tetrahydrobenzyl alcohol 2
5.2 g, 22.7 g of triethylamine and a catalytic amount of dimethylaminopyridine were added to 100 ml of dehydrated tetrahydrofuran.
The solution dissolved in ml was added dropwise and stirred at room temperature overnight. Triethylamine hydrochloride was filtered off, and about 2/3 of tetrahydrofuran was distilled off. The residue was diluted with 500 ml of methylene chloride, and a saturated aqueous solution of sodium hydrogen carbonate, 2 mol / l hydrochloric acid,
The organic phase was washed with a saturated saline solution, dried over anhydrous magnesium sulfate, and the solvent was distilled off. Further, it is purified by a silica gel column using chloroform as a solvent, and 4-methoxycarbonyloxybenzoic acid tetrahydrobenzyl ester 5
8.8 g (yield 99.3%, chemical purity> 97%) were obtained.

58.8 g of 4-methoxycarbonyloxybenzoic acid tetrahydrobenzyl ester, 700 ml of tetrahydrofuran and 70 ml of 25% aqueous ammonia were charged into a flask and stirred at room temperature for 1 hour. After the reaction solution was neutralized with concentrated hydrochloric acid and filtered, the solvent was distilled off. After adding 2000 ml of methylene chloride and washing the organic phase twice with 1000 ml of water, the solvent was distilled off and 37.8 g of 4-hydroxybenzoic acid tetrahydrobenzyl ester (80.4% yield,
Chemical purity> 95%).

4-methoxycarbonyloxybenzoic acid 1
4.8 g, 4-hydroxybenzoic acid tetrahydrobenzyl ester 18.4 g, a catalytic amount of dimethylaminopyridine and 330 ml of methylene chloride were charged into a flask, and while stirring, dicyclohexylcarbodiimide 1 was added thereto.
30 g of a solution prepared by dissolving 7.1 g of methylene chloride in 30 ml
Dropped over minutes. After stirring at room temperature for 20 minutes as it is, the reaction solution was filtered, and the organic phase was washed with 0.5 mol / l hydrochloric acid, a saturated aqueous solution of sodium hydrogencarbonate and saturated saline, dried over anhydrous magnesium sulfate, and the solvent was distilled off. 34.1 g of 4-methoxycarbonyloxybenzoic acid-p-tetrahydrobenzoxycarbonylphenyl ester (yield> 9)
9%, chemical purity 88%).

4-methoxygarbonyloxybenzoic acid
34.1 g of p-tetrahydrobenzoxycarbonylphenyl ester, 500 ml of tetrahydrofuran and 2
50 ml of 5% aqueous ammonia was charged into the flask and stirred at room temperature for 1 hour. After the reaction solution was filtered and the solvent was distilled off,
500 ml of methylene chloride is added and the organic phase is
After drying twice with anhydrous magnesium sulfate, the solvent was distilled off, and 27.7 g of 4-hydroxybenzoic acid-p-tetrahydrobenzoxycarbonylphenyl ester was obtained (97.1% yield, 93% chemical purity). I got

27.3 g of 4-hydroxybenzoic acid-p-tetrahydrobenzoxycarbonylphenyl ester,
4- (2-propenoyloxyethoxy) benzoic acid 1
9.2 g, a catalyst amount of dimethylaminopyridine, a small amount of butylhydroxytoluene (polymerization inhibitor) and 500 ml of methylene chloride were charged into a flask, and a solution obtained by dissolving 17.6 g of dicyclohexylcarbodiimide in 30 ml of methylene chloride was stirred for 30 minutes. It dripped over.
Stir at room temperature overnight, filter the reaction and filter
After dilution by adding 0 ml, the organic phase was washed with 0.5 mol / l hydrochloric acid, a saturated aqueous solution of sodium bicarbonate and saturated saline, dried over anhydrous magnesium sulfate, and the solvent was distilled off. Recrystallization from 700 ml of isopropanol gave 24.6 g of a crosslinked nematic liquid crystal monomer (yield 56%, chemical purity 99%).

Production Example 3 (Synthesis of Crosslinked Nematic Liquid Crystal Polymer (a))

Embedded image 5.00 g of the nematic liquid crystal monomer obtained in Production Example 1,
Crosslinkable nematic liquid crystal monomer 0.5 obtained in Production Example 2
19 g and 50 ml of a mixed solvent of dimethylacetamide / tetrahydrofuran = 4/1 (weight ratio) were charged into a flask, and the system was purged with nitrogen. On a water bath, bring the solution to a temperature of 5
After heating to 7 ° C. to dissolve the liquid crystal monomer, a solution prepared by dissolving 0.106 g of azobisisobutyronitrile in 2 ml of a mixed solvent of dimethylacetamide / tetrahydrofuran = 4/1 (weight ratio) was added dropwise. Solution temperature 57 ° C
The mixture was stirred for 6 hours while being purged with nitrogen, and allowed to cool to room temperature.
The polymer was precipitated by charging the solution into the ml. The polymer was collected by filtration, washed with a mixed solvent of methanol / tetrahydrofuran = 3/2 (weight ratio), dried under reduced pressure, and 4.78 g of the desired crosslinked nematic liquid crystal polymer (87% yield, weight average molecular weight 10,000). I got In addition, the polymer in Chemical formula 27 is conveniently represented by a block copolymer, and the copolymerization ratio (mol%) is shown below the repeating unit.

Production Example 4 (Synthesis of monomer (b1) imparting cholesteric properties)

Embedded image 10.0 g of isosorbide and p-toluenesulfonic acid were placed in 100 ml of tetrahydrofuran, and while stirring at room temperature, a solution of 5.76 g of dividropyran dissolved in 50 ml of tetrahydrofuran was added dropwise over 1.5 hours. After stirring at room temperature for 1.5 hours, the solvent was distilled off and dissolved in 250 ml of methylene chloride to give 1 mol / l.
The extract was washed with hydrochloric acid, a saturated aqueous solution of sodium hydrogen carbonate and saturated saline, and the organic phase was dried over anhydrous magnesium sulfate. The solvent was distilled off, and methylene chloride / diethyl ether = 1/1
Purification by silica gel column chromatography using (weight ratio) as a developing solvent gave 4.79 g (yield 30%) of a compound in which one side of a hydroxyl group of dihydropyran was protected.

Next, 4.21 g of isosorbide having a hydroxyl group protected on one side, 2.96 g of p-cyanobenzoic acid, a catalytic amount of dimethylaminopyridine and 110 ml of ethyl acetate were charged into a flask, and while stirring, dicyclohexylcarbodiimide was added to the flask. A solution in which 52 g was dissolved in 5 ml of ethyl acetate was added dropwise. The mixture was stirred at room temperature for 2 hours, filtered, diluted with 50 ml of ethyl acetate, washed with 1 mol / l hydrochloric acid, a saturated aqueous solution of sodium bicarbonate and brine, and the organic phase was dried over anhydrous magnesium sulfate. The solvent was distilled off to obtain a cyanophenyl ester of isosorbide having a hydroxyl group protected on one side (chemical purity: 83%).

7.44 g of a cyanophenyl ester of isosorbide protected with one hydroxyl group was added to 75 ml of tetrahydrofuran.
, And refluxed.
Refluxed for 5 minutes. The tetrahydrofuran was distilled off, the residue was dissolved in 200 ml of methylene chloride, and the organic phase was washed with saturated saline and dried over anhydrous magnesium sulfate. Methylene chloride / diethyl ether = 6/1 to 0/1 as a developing solvent
(Weight ratio), purification was carried out by silica gel column chromatography to obtain 4.63 g (yield 91%, chemical purity 97%) of cyanophenyl ester of isosorbide from which the hydroxyl-protecting group was removed.

4- (2-propenoyloxyethoxy)
2.55 g of benzoic acid, 2.83 g of cyanophenyl ester of isosorbide, a catalytic amount of dimethylaminopyridine and 70 ml of methylene chloride are charged into a flask, and 2.33 g of dicyclohexylcarbodiimide is stirred at room temperature while stirring.
Was dissolved in 5 ml of methylene chloride. The mixture was stirred for 4.5 hours, filtered, and methylene chloride (130 m)
After diluting with 1 l, the organic phase was washed with 1 mol / l hydrochloric acid, saturated aqueous sodium hydrogen carbonate solution and saturated saline, and dried over anhydrous magnesium sulfate. The solvent was distilled off, and methylene chloride /
Purified by silica gel column chromatography using diethyl ether = 6/1 (weight ratio) as a developing solvent, 1.39 g of a monomer to give a desired cholesteric property (yield: 23)
%, Chemical purity 90%).

Production Example 5 (Synthesis of crosslinked nematic liquid crystal monomer (b2))

Embedded image 200 g of 4,4-biphenol, a small amount of concentrated hydrochloric acid and 2 L of tetrahydrofuran were charged into a flask, and 90.3 g of 3,4-dihydro-2H-pyran was added dropwise with stirring. The mixture was stirred for 2 hours as it was, and the reaction solution was adjusted to about pH 8 by adding triethylamine, and tetrahydrofuran was distilled off about 4/5. 2 L of methylene chloride and 2 L of a 2 mol / l aqueous sodium hydroxide solution were added thereto, followed by stirring, and the precipitated crystals were collected by filtration. The crystals are placed in 2 L of methylene chloride, and 30 ml of acetic acid is added thereto while stirring.
The pH was adjusted to about H4, and the organic phase was washed with a saturated aqueous solution of sodium hydrogencarbonate and saturated saline, dried over anhydrous magnesium sulfate, and then the solvent was distilled off to obtain 104 g of biphenol in which one side of a hydroxyl group was protected (yield). 35%, chemical purity 99
%).

4- (2-propenoyloxyethoxy)
2.55 g of benzoic acid, 2.92 g of biphenol protected on one side of the hydroxyl group, a catalytic amount of dimethylaminopyridine and 60 ml of methylene chloride were charged into a flask, and stirred at room temperature while dicyclohexylcarbodiimide was added.
A solution of 33 g dissolved in 5 ml of methylene chloride was added dropwise. After stirring for 16 hours, the reaction solution was filtered and diluted by adding 130 ml of methylene chloride, and the organic phase was washed with 1 mol / l hydrochloric acid, a saturated aqueous solution of sodium hydrogen carbonate and saturated saline, and dried over anhydrous magnesium sulfate. The solvent was distilled off. The crystal was recrystallized from 100 ml of isopropanol to obtain 4.80 g (88% yield, 98% chemical purity) of a hydroxy-protected liquid crystal monomer precursor.

[0086] 3.00 g of a liquid crystal monomer precursor having a protected hydroxyl group was dissolved in 45 ml of tetrahydrofuran, and 1 ml of concentrated hydrochloric acid was added thereto, followed by heating under reflux for 1 hour. After cooling to room temperature, tetrahydrofuran and excess hydrochloric acid were distilled off using a trap, and 30 ml of tetrahydrofuran was added to dissolve the remaining solids and the solvent was distilled off.
The solid content was dried under reduced pressure to obtain 2.45 g of a liquid crystal monomer precursor from which a hydroxyl-protecting group had been removed.

2.00 g of a liquid crystal monomer precursor,
0.624 g of 2,5,6-tetrahydrobenzoic acid, dimethylaminopyridine catalyst amount and a small amount of butylhydroxytoluene (polymerization inhibitor) and methylene chloride 30 ml
Was charged into a flask, and a solution of 1.12 g of dicyclohexylcarbodiimide dissolved in 2 ml of methylene chloride was added dropwise with stirring. After stirring for 16 hours, the reaction solution was filtered and diluted by adding 100 ml of methylene chloride.
The organic phase was washed with 0.5 mol / l hydrochloric acid, a saturated aqueous solution of sodium hydrogen carbonate, and saturated saline, dried over anhydrous magnesium sulfate, and the solvent was distilled off. 30 ml of isopropanol
From the crosslinked nematic liquid crystal monomer 2.0
5 g (yield 81%, chemical purity 96%) were obtained.

Production Example 6 (Synthesis of crosslinked cholesteric liquid crystal polymer (b))

Embedded image 5.00 g of the monomer imparting cholesteric properties obtained in Production Example 4, 0.391 g of the crosslinked nematic liquid crystal monomer obtained in Production Example 5, and 50 ml of a mixed solvent of dimethylacetamide / tetrahydrofuran = 4/1 (weight ratio)
Was charged into a flask, and the atmosphere in the system was replaced with nitrogen. After heating to a solution temperature of 57 ° C. on a water bath to dissolve the liquid crystal monomer, 0.0895 g of azobisisobutyronitrile was dissolved in 2 ml of a mixed solvent of dimethylacetamide / tetrahydrofuran = 4/1 (weight ratio). The solution was added dropwise. The mixture was stirred for 6 hours while being replaced with nitrogen while being heated to a solution temperature of 57 ° C., and allowed to cool to room temperature. Then, the reaction solution was filtered and poured into 1,000 ml of methanol to precipitate a polymer. The polymer was collected by filtration, and methanol / tetrahydrofuran = 3 /
After washing with a 2 (weight ratio) mixed solvent and drying under reduced pressure, 4.69 g (yield 87%, weight average molecular weight 10,000) of the desired crosslinked cholesteric liquid crystal polymer was obtained. In addition, the polymer in Chemical formula 30 is conveniently represented by a block copolymer,
The copolymerization ratio (mol%) is shown below the repeating unit.

Production Example 7 (Synthesis of monomer (c) imparting cholesteric properties)

Embedded image 122 g of p-hydroxybenzaldevide was added to toluene 1
After heating and dissolving in 200 ml, (S)-(-)-1
121 g of phenylethylamine are added over 30 minutes,
Reflux for about 3-4 hours until the theoretical amount of water is confirmed using a Dean-Stark apparatus. Next, the reaction solution was allowed to cool, and the precipitated crystals were filtered and recrystallized with 1500 ml of ethanol to obtain 166 g of self-colored needle-like crystals (chiral phenol compound).
was gotten.

4- (2-propenoyloxyethoxy)
Benzoic acid 118 g, chiral phenol compound 113 g,
A catalyst amount of dimethylaminopyridine and a small amount of butylhydroxytoluene were dissolved in 2500 ml of ethyl acetate, stirred at room temperature, and 124 g of dicyclohexylcarbodiimide (DCC) dissolved in 200 ml of ethyl acetate was gradually added thereto. After stirring at room temperature for 5 hours, the deposited DC
C urea was filtered off. The filtrate was washed with a saturated aqueous sodium hydrogen carbonate solution and saturated saline (twice) (100 ml each),
Further, after drying over magnesium sulfate, filtration and removal of the solvent, the residue was recrystallized with 1800 ml of ethanol to obtain 130 g of a monomer having a desired cholesteric property (chemical purity> 90%).

Comparative Production Example 1 The same polymerization as in Production Example 3 was carried out except that the crosslinked nematic liquid crystal monomer obtained in Production Example 2 was not used, and the nematic liquid crystal polymer (weight average molecular weight) was used. 10,000).

Example 1 Cross-linked nematic liquid crystal polymer 1 obtained in Production Example 3
00 parts by weight, 13 parts by weight of the crosslinked cholesteric liquid crystal polymer obtained in Production Example 6 and 21 parts by weight of the cholestericity-imparting monomer obtained in Production Example 7 are dissolved in cyclohexanone to obtain a 30% by weight liquid crystal composition. Was prepared.

Next, a polyvinyl alcohol aqueous solution is applied on a glass plate by spin coating, and dried at 170 ° C. for 1 hour to form a 0.1 μm-thick thin film. A prepared alignment plate was prepared.

On the alignment plate, the solution of the liquid crystal composition was applied by a spin coater, dried, heated at 160 ° C. for 5 minutes, subjected to alignment treatment, allowed to cool at room temperature, and then irradiated with an electron beam. Irradiation was carried out at 40 Mrad / cm ² to crosslink, and an oriented film subjected to orientation crosslinking treatment was obtained.

Example 2 To a solution containing 100 parts by weight of the liquid crystal composition prepared in Example 1 was added a solution of a liquid crystal composition in which 5 parts by weight of a photoacid generator was added. After performing the same alignment treatment, the Dee is passed through a photomask having three regions having transmittances of 100%, 50%, and 0% at a pitch of 100 μm.
After irradiation with p-ultraviolet light at 100 mJ / cm ² , and re-orientation under the same orientation treatment conditions as described above and performing multicolor reflection treatment,
An electron beam was irradiated at 40 Mrad / cm ² to perform a cross-linking treatment, thereby obtaining an oriented film (a multicolor reflector) subjected to an orientation-cross-linking treatment. The resulting multicolor reflector had three regions of 450 nm, 540 nm, and 620 nm at the center of the reflected light with respect to the center wavelength.

Comparative Example 1 The procedure of Example 1 was repeated, except that the nematic liquid crystal polymer obtained in Comparative Production Example 1 was used instead of the crosslinked nematic liquid crystal polymer obtained in Production Example 3. The operation was performed to obtain an oriented film.

Comparative Example 2 An alignment film was obtained in the same manner as in Example 1, except that the liquid crystal composition was prepared without using the cholestericity-imparting monomer obtained in Production Example 6. Was.

Comparative Example 3 The same procedure as in Example 2 was carried out except that the nematic liquid crystal polymer obtained in Comparative Production Example 1 was used instead of the crosslinked nematic liquid crystal polymer obtained in Production Example 3. The operation was performed to obtain an oriented film.

Comparative Example 4 An alignment film was obtained in the same manner as in Example 2 except that the liquid crystal composition was prepared without using the monomer imparting cholesteric properties obtained in Production Example 7. Was.

Reference Example 1 In Example 1, except that the electron beam irradiation was not performed,
The same operation as in Example 1 was performed to obtain an oriented film.

Reference Example 2 In Example 2, except that electron beam irradiation was not performed,
The same operation as in Example 2 was performed to obtain an oriented film.

The oriented films obtained in Examples and Comparative Examples were heated at various temperatures for 1 hour, and changes in appearance were visually observed. The highest temperature at which no change was observed was evaluated as the heat resistant temperature. Table 1 shows the results.

[0103]

[Table 1] From Table 1, the alignment film of the example prepared from the liquid crystal composition containing the cross-linked nematic liquid crystal polymer (a), the cross-linked cholesteric liquid crystal polymer (b) and the monomer (c) for imparting cholesteric property is as follows: It can be seen that the heat resistance temperature is significantly improved as compared with the alignment film of the comparative example obtained from the liquid crystal composition not containing one of these. Further, from the reference example, it is recognized that the heat resistance temperature of the oriented film is significantly improved by performing the crosslinking treatment.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) G02B 5/20 101 G02B 5/20 101 4J002 5/30 5/30 4J011 G02F 1/13 505 G02F 1/13 505 4J027 1/1335 520 1/1335 520 1/13363 1/13363 (72) Inventor Sadahiro Nakanishi 1-2-1, Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation (72) Inventor Shu Mochizuki Ibaraki, Osaka 1-1-2 Shimohozumi Ichito F-term in Nitto Denko Corporation (reference) 2H048 AA06 AA09 AA12 AA19 AA22 BA04 BA64 BB02 BB14 BB42 2H049 BA03 BA06 BA46 BB43 BC04 BC09 BC22 2H088 GA02 GA03 HA15 HA21 JA14 MA20 LA027 HA11 BA02 BA13 BD01 4J002 BG07W BG07X EH076 FD146 4J011 AC04 QA03 QA33 QA38 QA44 QA45 QA46 QB02 QB03 UA01 UA03 UA06 VA01 WA10 4J027 AA01 AA02 CC03 CD04 CD05

Claims (8)

[Claims] 1. General formula (a1): (Wherein R ¹ represents a hydrogen atom or a methyl group, A and D
Each independently represents a cyclic functional group, and X represents -COO-
A group, —OCO— or —O—, E represents a cyano group, an alkyl group, an alkoxy group, a hydroxy group, a chlorine atom or a fluorine atom, and g represents an integer of 2 to 6. And a repeating unit represented by the general formula (a2): (Wherein R ¹ represents a hydrogen atom or a methyl group, A and D
Each independently represents a cyclic functional group; X each independently represents a -COO- group, -OCO- group or -O- group;
Represents a crosslinking group, h represents an integer of 2 to 6, and k represents an integer of 0 to 6. A) a cross-linked nematic liquid crystal polymer having a repeating unit represented by formula (a), and a general formula (b1): (Wherein R ¹ represents a hydrogen atom or a methyl group, A and D
Each independently represents a cyclic functional group; X each independently represents a -COO- group, -OCO- group or -O- group;
Is an optically active group that is not modified or deactivated by actinic light,
E represents a cyano group, an alkyl group, an alkoxy group, a hydroxy group, a chlorine atom or a fluorine atom, and r represents an integer of 2 to 6. ) And a general formula (b)
2): embedded image (Wherein R ¹ represents a hydrogen atom or a methyl group, A and D
Each independently represents a cyclic functional group; X each independently represents a -COO- group, -OCO- group or -O- group;
Represents a crosslinking group, h represents an integer of 2 to 6, and k represents an integer of 0 to 6. A) a cross-linked cholesteric liquid crystal polymer having a repeating unit represented by formula (b), and a general formula (c): (Wherein R ¹ represents a hydrogen atom or a methyl group, A and D
Each independently represents a cyclic functional group, and X represents -COO-
A group, -OCO- group or -O- group, J represents an optically active group which is modified or deactivated by actinic rays, and w represents an integer of 2-6. A cholesteric liquid crystal composition containing a monomer (c) for imparting cholesteric properties represented by the formula (1). 2. A in the general formulas (a1), (a2), (b1), (b2) and (c)
And D (cyclic functional group) are represented by the general formula: The cholesteric liquid crystal composition according to claim 1, which is any one of the cyclic functional groups represented by 3. G (crosslinking group) in the general formulas (a2) and (b2) is represented by the following general formula: ( ¹ ) wherein R ¹ represents a hydrogen atom or a methyl group;
Or the cholesteric liquid crystal composition according to 2. 4. In the general formula (b1), L (an optically active group which is not modified or deactivated by actinic rays) is represented by the general formula: (In each formula, t and u are 0 ≦ t ≦ 5, 1 ≦ u ≦ 6, and t
Indicates an integer satisfying + 1 ≦ u. The optically active group (l) represented by the formula (1):
3. The cholesteric liquid crystal composition according to any one of 3. 5. The method according to claim 1, wherein J in the general formula (c) is
An optically active group which is modified or deactivated) has the general formula:(In each formula, R^Two Represents a phenyl group, a biphenyl group, 1-naph
A tyl group or a 2-naphthyl group;^Three Is a methyl group,
A phenyl group or a carboxymethyl group; ^Four Hame
It represents a tyl group, a benzyl group or a t-butyl group. * Is not
Shows asymmetric carbon atoms. The optically active group (l) represented by
5. Any of claims 1 to 4, wherein
3. The cholesteric liquid crystal composition according to item 1. 6. An alignment film obtained by subjecting the cholesteric liquid crystal composition according to claim 1 to an alignment treatment and a crosslinking treatment. 7. The cholesteric liquid crystal composition according to claim 1, wherein the cholesteric liquid crystal composition is irradiated with actinic rays controlled for each of a plurality of regions sequentially or simultaneously. A plurality of regions having different effective contents of active groups were formed, and thereafter, or simultaneously, a cholesteric liquid crystal composition was subjected to an alignment treatment to form a reflection region having a different reflection wavelength for each of the regions. Thereafter, a method for producing a multicolor reflector, which is further subjected to a crosslinking treatment. 8. A multicolor reflector obtained by the method according to claim 7.