JP2000327720A - Side chain type liquid crystal polymer, retardation plate and elliptically polarizing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new side chain type liquid crystal polymer which can be inclinedly oriented with respect to a film surface when forming a film, a retardation plate comprising a film formed of the side chain type liquid crystal polymer, and a use thereof. Elliptically polarizing plates are provided. SOLUTION: In the side chain type liquid crystal polymer composed of a monomer unit having a liquid crystal side chain, (a) a monomer unit having a hydroxyl group at a terminal is included as the monomer unit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a side chain type liquid crystal polymer having a tilt alignment property, a retardation plate comprising a film formed of the side chain type liquid crystal polymer, and an elliptically polarizing plate using the same.

[0002]

2. Description of the Related Art As liquid crystal displays have been improved in display performance, the range of applied products has been expanded from small monochrome displays such as calculators and clocks to large color displays such as notebook computers, televisions and monitors. Recently, some characteristics, for example, those exceeding the CRT in definition have appeared.

[0003] However, CR displays are used in liquid crystal displays.
There is a disadvantage that the viewing angle is narrower than T. For this reason, several techniques have been proposed as techniques for increasing the viewing angle of a liquid crystal display. For example, a method in which pixels are divided into a plurality of regions having different alignment directions of liquid crystal molecules and averaged, such as an alignment division method and a halftone method, IPS,
A method for improving a liquid crystal operation mode such as MVA and OCB, a method using a condenser lens or a diffusion lens, a method using a retardation plate serving as a viewing angle compensation film, and the like have been proposed.

[0004] Among these methods, a method for improving the liquid crystal operation mode and a method using a phase difference plate have been put to practical use.
In particular, the method using a retardation plate can increase the viewing angle by simply bonding a liquid crystal panel with an integrated polarizing plate and retardation plate without changing the liquid crystal panel. It is not necessary to change the production line, and the cost is lower than the method of improving the liquid crystal mode.

As such a retardation plate, those in which a discotic liquid crystal is tilted and those in which a rod-shaped nematic liquid crystal is tilted are known. In each case, a liquid crystal polymer in which a liquid crystal polymer is tilted is used. ing. Various types of liquid crystal polymers are disclosed in Japanese Patent Application Laid-Open Nos. 8-5838 and 7-20434 regarding a retardation plate composed of a liquid crystal polymer that is tilted and aligned. The polymer is disclosed, and the latter mainly discloses a main chain type liquid crystal polymer.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel side-chain type liquid crystal polymer which can be inclinedly oriented with respect to the film surface during film formation, and a retardation comprising a film formed of the side-chain type liquid crystal polymer. A plate and an elliptically polarizing plate using the same.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, a film obtained from a side chain type liquid crystal polymer containing a specific monomer unit shown below is formed on the film surface. On the other hand, they have found that they are tilted, and completed the present invention.

That is, the side chain type liquid crystal polymer of the present invention is a side chain type liquid crystal polymer composed of a monomer unit having a liquid crystal side chain, wherein (a) a monomer unit having a hydroxyl group at a terminal is used as the monomer unit. It is characterized by including.

In the above, it is preferable that the (a) monomer unit having a hydroxyl group at the terminal is a monomer unit represented by the following general formula (a1).

It is preferable that (a) the monomer unit having a hydroxyl group at the terminal contains 20 to 50 mol% of the monomer unit having a liquid crystal side chain.

Further, the monomer unit having a liquid crystal side chain preferably contains a monomer unit having a cyano group at a terminal (b) represented by the following general formula (b1).

The side chain type liquid crystal polymer of the present invention preferably has a weight average molecular weight of 2,000 to 100,000.

On the other hand, a retardation plate of the present invention is a film comprising the side chain type liquid crystal polymer described in any of the above, wherein the orientation direction of the side chain type liquid crystal polymer is inclined with respect to the film surface of the film. The film used is

On the other hand, the elliptically polarizing plate of the present invention is obtained by laminating and integrating the above retardation plate with a polarizing plate.

[Effects] According to the side chain type liquid crystal polymer of the present invention, as shown in the results of the examples, (a) a monomer unit having a hydroxyl group at a terminal is included, so that the film is tilted with respect to the film surface during film formation. Can be done.
Therefore, by using such a liquid crystal polymer, it is possible to obtain a retardation plate and an elliptically polarizing plate having an inclined optical axis, which are effective in compensating for a viewing angle. The details of the reason why the side-chain type liquid crystal polymer of the present invention has the tilt orientation are not clear, but it is assumed that the terminal hydroxyl groups of the liquid crystal side chains are localized at the air-side interface during film formation, thereby causing the tilt alignment. Is done.

When the (a) monomer unit having a hydroxyl group at the terminal is a monomer unit represented by the following general formula (a1), the side chain type liquid crystal polymer tends to exhibit a tilt alignment property.

When (a) the monomer unit having a hydroxyl group at the terminal is contained in an amount of 20 to 50 mol% of the monomer unit having a liquid crystalline side chain, it is preferable to maintain the uniformity of orientation of the side chain type liquid crystal polymer. It is possible to obtain a proper tilt orientation.

When the monomer unit having a liquid crystal side chain contains a monomer unit having a cyano group at the terminal (b) represented by the following general formula (b1), (a) a hydroxyl group at the terminal Since the compound has a chemical structure similar to that of the monomer unit having the formula (1), the above-described inclined orientation can be obtained more reliably.

When the weight average molecular weight of the side chain type liquid crystal polymer of the present invention is from 2,000 to 100,000, uniform alignment can be obtained while maintaining good film formability.

On the other hand, since the retardation plate of the present invention is composed of the side chain type liquid crystal polymer as described above, it is effective for viewing angle compensation.
A retardation plate having an inclined optical axis can be used.

On the other hand, according to the elliptically polarizing plate of the present invention, since the above-mentioned retardation plate is laminated on the polarizing plate, the viewing angle can be suitably compensated only by sticking to the liquid crystal panel.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION The side chain type liquid crystal polymer of the present invention comprises
A side chain type liquid crystal polymer composed of a monomer unit having a liquid crystal side chain, and as the monomer unit, (a) a monomer containing a monomer unit having a hydroxyl group at a terminal can be used without particular limitation.

(A) Examples of the monomer unit having a hydroxyl group at the terminal include a compound represented by the following general formula (a1):

Embedded image (Wherein, R ¹ represents a hydrogen atom or a methyl group, and X ¹ represents —C
An OO- group or an -OCO- group, m is an integer of 1 to 6,
p and q are each independently 1 or 2 (provided that p + q =
Satisfies ≦ 3. ). )). The (a) monomer unit having a hydroxyl group at the terminal represented by the general formula (a1) is represented by R ¹
Is a hydrogen atom, X ¹ is a —COO— group, m is an integer of 2 to 6,
It is preferable that p is 1 and q is 2.

The proportion of (a) the monomer unit having a hydroxyl group at the terminal in the side chain type liquid crystal polymer of the present invention is 20 to 50 mol% of the monomer unit having a liquid crystal side chain constituting the side chain type liquid crystal polymer. It is. (A) Since the side-chain type liquid crystal polymer tends to be difficult to take a tilted alignment when the proportion of the monomer unit having a hydroxyl group at the end is reduced, the proportion of the monomer unit having the hydroxyl group at the end is 35 mol%. It is more preferable to make the above. On the other hand, when the proportion of (a) the monomer unit having a hydroxyl group at the terminal increases, the orientation of the side chain type liquid crystal polymer tends to decrease and uniformity cannot be maintained. Is more preferably not more than 45 mol%.

The monomer unit having a liquid crystal side chain constituting the side chain type liquid crystal polymer together with the monomer unit having a hydroxyl group at the terminal (a) is not particularly limited. Since it is preferable to exhibit a nematic liquid crystal property having a dielectric anisotropy of, the monomer unit having a liquid crystal side chain is preferably a monomer unit having a nematic liquid crystal property. The monomer unit exhibiting nematic liquid crystallinity is 50 to 80 mol% of the monomer unit having a liquid crystal side chain constituting the side chain type liquid crystal polymer, and (a) a monomer unit other than a monomer unit having a hydroxyl group at a terminal is used. Constitute. . As the monomer unit exhibiting nematic liquid crystallinity, (b) a monomer unit having a cyano group at the terminal is particularly preferable. In addition, (b) a monomer unit having a nematic liquid crystal property other than a monomer unit having a cyano group at the terminal includes (c) a monomer unit having an optically active group and (d) a monomer unit having a terminal crosslinking group, These monomer units are preferably used, if necessary, in a range of 50 mol% or less of the monomer units of the side chain type liquid crystal polymer.

Examples of the monomer unit (b) having a cyano group at the terminal include those represented by the following general formula (b1):

Embedded image (Wherein, R ² represents a hydrogen atom or a methyl group, and X ² represents —C
An OO- group or an -OCO- group, j is an integer of 1 to 6,
s and t are each independently 1 or 2 (provided that s +
It satisfies t ≦ 3. ))).

The monomer unit (c) having an optically active group includes, for example, a compound represented by the following general formula (c1):

Embedded image (Wherein, R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents

Embedded image (Where R ⁵ is

Embedded image X ³ represents a —COO— group or —OCO— group, and k represents a positive integer of 1 to 6).

Examples of the monomer unit (d) having a terminal cross-linking group include those having an unsaturated double bond such as an acryloyl group or a cyclohexene ring at the terminal of the side chain of the monomer unit.

The side-chain type liquid crystal polymer is prepared by preparing various acrylic or methacrylic liquid crystal monomers corresponding to each of the above monomer units (hereinafter simply referred to as (meth) acrylic liquid crystal monomers) by, for example, a radical polymerization method or a cationic polymerization method. It can be carried out by copolymerizing according to a polymerization method of a usual (meth) acrylic liquid crystal monomer such as a polymerization method and an anion polymerization method. However, (a)
When it is necessary to protect the terminal hydroxyl group at the stage of preparing the (meth) acrylic liquid crystal monomer corresponding to the monomer unit having a hydroxyl group at the terminal, a (meth) acrylic liquid crystal monomer having a protected hydroxyl group is copolymerized. By removing the protective group after producing the side chain type liquid crystal polymer by the above method, (a) a monomer unit having a hydroxyl group at a terminal can be introduced into the side chain type liquid crystal polymer. In the monomer unit (d) having a terminal cross-linking group, the terminal cross-linking group is simultaneously polymerized when the corresponding (meth) acrylic liquid crystal monomer is polymerized. After the liquid crystal polymer is produced, (a) a monomer unit having a terminal cross-linking group is introduced into the side chain type liquid crystal polymer by reacting acryloyl chloride or the like with a hydroxyl group of a monomer unit having a hydroxyl group at a terminal. Is preferred.

When the radical polymerization method is applied,
Various polymerization initiators can be used, and among them, azobisisobutyronitrile and benzoyl peroxide, which decompose at an intermediate temperature that is neither high nor low, are preferable.

The molecular weight of the side chain type liquid crystal polymer is usually set to about 2,000 to 100,000 based on the weight average molecular weight. Further, when the weight average molecular weight is too small, the film forming property of the side chain type liquid crystal polymer film formed on the substrate when preparing the retardation plate becomes poor, so that the weight average molecular weight is not less than 2,500. It is preferred that On the other hand, if the weight-average molecular weight is excessive, the alignment as a liquid crystal, in particular, monodomain formation via a rubbing alignment film or the like is poor, and it is difficult to form a uniform alignment state. Is preferred.

As a method for forming a film in which the orientation direction of the liquid crystal polymer is inclined with respect to the obtained film surface from the side chain type liquid crystal polymer of the present invention, a method according to a conventional orientation treatment can be employed.

As such a method, for example, an alignment film made of polyimide, polyvinyl alcohol, or the like is formed on a substrate, rubbed with a rayon cloth or the like, and then a liquid crystal polymer is spread thereon. After the glass transition temperature or more, heating to less than the isotropic phase transition temperature to tilt-align the molecules of the liquid crystal polymer, and then cooled to less than the glass transition temperature in the tilted state to a glass state,
A method of fixing the orientation of the liquid crystal polymer to form a film and the like can be given. In this method, from the viewpoint of the efficiency of the alignment treatment, it is preferable to heat the alignment treatment to a temperature that is 30 to 70 ° C., particularly about 50 ° C. higher than the glass transition temperature of the liquid crystal polymer.

As the substrate, an inorganic material such as a glass plate or a polymer material such as a plastic film can be used. As the plastic substrate, triacetyl cellulose, polycarbonate, polysulfone, polyethersulfone, polyethylene terephthalate and the like are preferable.

As a method of aligning the liquid crystal polymer, a method using a stretched film as an alignment film instead of the above-described method of rubbing the alignment film, or a method of irradiating a polymer or polyimide containing cinnamate or azobenzene with polarized ultraviolet light is used. A method used as an alignment film can also be adopted.

The liquid crystal polymer can be spread on the substrate by a heating and melting method, or can be developed as a solution dissolved in a solvent. As the solvent, for example, methylene chloride, cyclohexanone, trichloroethylene, tetrachloroethane, N-methylpyrrolidone, tetrahydrofuran, dimethylformamide and the like can be appropriately selected and used. In the development, a coating machine such as a Noah coater, a spinner, or a roll coater can be appropriately used.

After the side-chain type liquid crystal polymer is formed into a film and then oriented, if necessary, (d) the terminal cross-linking group of the monomer unit having a terminal cross-linking group is cross-linked to form a side-chain type liquid crystal polymer. The orientation can be further fixed. Electromagnetic waves such as UV and electron beams can be used for crosslinking. In particular, cross-linking by electron beam irradiation is advantageous because it does not require an initiator that tends to lower the orientation of the liquid crystal polymer.

The thickness of the liquid crystal polymer film formed on the substrate may be appropriately adjusted depending on the characteristics of the liquid crystal cell to be compensated, and is usually about 0.1 to 10 μm, especially 0.2 to 3 μm. preferable.

In the film made of the liquid crystal polymer composition formed on the substrate by performing the alignment treatment as described above, the alignment direction of the liquid crystal polymer composition is inclined with respect to the film surface, and the film is used to compensate for the viewing angle of the liquid crystal cell. Used as a phase difference plate. The retardation plate is arranged on one side or both sides of the liquid crystal cell. Further, a structure in which a plurality of retardation plates are stacked may be employed. In this case, the retardation may be stacked with the direction of the slow axis of the plate surface shifted (for example, two retardation plates are orthogonalized).

Such a retardation plate can be used alone for a liquid crystal cell, but can also be used as an elliptically polarizing plate which is laminated with a polarizing plate. Although the position of the elliptically polarizing plate with respect to the liquid crystal cell is not particularly limited, it is general that the retardation plate is disposed between the polarizing plate and the liquid crystal cell.

As the polarizing plate, those having a polarizing function can be used without particular limitation. Specifically, a hydrophilic polymer film such as a polyvinyl alcohol-based film, a partially formalized polyvinyl alcohol-based film, an ethylene-vinyl acetate copolymer-based partially saponified film, and the like were stretched by absorbing iodine and a dichroic dye. And a protective film layer of triacetyl cellulose or the like provided on a polyene oriented film such as a dehydrated product of polyvinyl alcohol or a dehydrochlorinated product of polyvinyl chloride. These can be appropriately selected and used. The thickness of the polarizing plate is not particularly limited, but is usually preferably about 100 to 250 μm.

The phase difference plate and the polarizing plate are usually bonded together.
When birefringence occurs in the alignment film on which the phase difference plate is formed, the phase difference plate is bonded to the polarizing plate by transfer. On the other hand, when the alignment film on which the retardation film is formed is a substrate having a small birefringence such as triacetyl cellulose, the film formed on the substrate is directly used as a retardation film and used by bonding to a polarizing plate. You can also. A substrate such as triacetyl cellulose bonded to a polarizing plate together with a retardation plate is used as a protective film for the polarizing plate. In addition, the bonding angle of the polarizing plate and the retardation plate in producing the elliptically polarizing plate can be arbitrarily selected. Also,
For bonding the retardation plate and the polarizing plate, an adhesive can be used as necessary.

The elliptically polarizing plate can also be manufactured by directly forming a retardation plate (a film with a tilt orientation) on the polarizing plate.

[0044]

EXAMPLES The present invention will be described in detail below with reference to synthesis examples and examples, but the present invention is not limited to these examples.

Synthesis Example (1): (a) Synthesis of Monomer Having Hydroxyl Group at Terminal

Embedded image In a 3 liter three-necked flask, 4,4′-biphenol (200 g, 1.08 mol) was dissolved in 2 liters of tetrahydrofuran (hereinafter referred to as THF), and 12N hydrochloric acid was added while stirring at room temperature. Was added in 10 drops.
There, 3,4-dihydro-2H pyran (90.3 g,
1.08 mol, DHP in the formula) was added dropwise over 45 minutes and stirred overnight. Next, triethylamine was added to the reaction solution to adjust the pH to about 8, and the solvent THF was reduced to 4/5.
After distilling off, 2 liters of methylene chloride was added. Further, when 2 L of a 2N aqueous sodium hydroxide solution was added and stirred, a glossy white precipitate was formed. This precipitate was separated by filtration, and dispersed again in methylene chloride.
Was added to neutralize the salt to pH4. After further adding methylene chloride and THF so as to completely dissolve, the extract was washed with a saturated aqueous solution of sodium hydrogen carbonate and a saturated saline solution (1 liter each), and dried over anhydrous magnesium sulfate. The solvent was distilled off to obtain a white powder of 4- (4′-hydroxybiphenyl) tetrahydropyranyl ether (where THP represents a tetrahydropyranyl group) (yield 290.4 g,
Yield 58%, purity 92%).

Next, in a 3-liter eggplant flask,
4- (4'-hydroxybiphenyl) tetrahydropyranyl ether (170.7 g, 631 mmol),
(2-propenoyloxyethoxy) benzoic acid (15
8.1 g, 669 mmol), dimethylaminopyridine (8.07 g, 66 mmol, DMAP in the formula), butylhydroxytoluene as a small amount of a polymerization inhibitor and 2.5 l of methylene chloride were charged into a solution. Dicyclohexylcarbodiimide (138.0 g, 669 mmol, DC
C) was added little by little and stirred overnight. After the precipitated DC urea was separated by filtration, methylene chloride was added to make the total volume 1 liter, and the filtrate was washed with 0.5N hydrochloric acid, a saturated aqueous solution of sodium hydrogen carbonate, and a saturated saline solution, and dried over anhydrous magnesium sulfate. The solvent was distilled off. The crude product was dissolved in a heated mixed solvent consisting of 2.5 liters of isopropyl alcohol and 250 ml of toluene, filtered through celite, cooled to room temperature, and recrystallized to protect the terminal hydroxyl group shown in Chemical formula 8 with THP. (186.3 g, 57%, 96% purity) (2): (b) Synthesis of a monomer having a cyano group at the terminal

Embedded image Potassium hydroxide alcoholic aqueous solution (potassium hydroxide 3
00g, ethanol 700ml, water 300ml)
-Hydroxybenzoic acid (276 g, 2 mol) and a catalytic amount of potassium iodide were added and dissolved. Ethylene chlorohydrin (177 g, 2.2 mol) was slowly added while heating, and the mixture was refluxed for about 15 hours. Potassium chloride was precipitated with the reaction. After completion of the reaction, ethanol was distilled off, and the reaction solution was added to 2 liters of water. After washing the reaction aqueous solution twice with diethyl ether, the aqueous layer was acidified with 4N hydrochloric acid.
The obtained precipitate was filtered, dried and then recrystallized from ethanol to give 4- (2-hydroxyethoxy) benzoic acid (yield 2).
90 g, yield 82%, purity 98%).

Next, 4- (2-hydroxyethoxy)
Benzoic acid (182 g, 1 mol), hydroquinone (40
g), a solution of p-toluenesulfonic acid (40 g) and acrylic acid (600 ml) dissolved in a 1/1 mixed solvent of benzene / toluene (600 ml) was added to Dean-St.
The mixture was refluxed (about 15 hours) until the theoretical amount of water was separated using an ark tube. The reaction solution was placed in 4 liters of diethyl ether and washed with warm water. After washing with a saturated saline solution, the mixture was dried over anhydrous sodium sulfate. Evaporate the solvent,
The obtained solid was recrystallized from acetone / hexane to give 4-
(2-propenoyloxyethoxy) benzoic acid (yield 1
53 g, yield 65%, purity 97%).

Then, the mixture was dissolved in 4- (2-propenoyloxyethoxy) benzoic acid (23.6 g, 0.1 mol) in 400 ml of acetone, and further dissolved in trifluoroacetic anhydride (20.8 ml, 0.1 mol). 15 mol) and stirred. To the reaction solution was added 4-cyano-4'-hydroxybiphenyl (19.5 g, 0.1 mol), and the mixture was reacted at room temperature for 6 hours. Acetone was distilled off from the reaction solution, and the mixture was dissolved by adding diethyl ether, washed with water, a saturated aqueous solution of sodium hydrogen carbonate and saturated saline, and then dried over anhydrous sodium sulfate. The solvent was distilled off, and the obtained solid was recrystallized from 600 ml of acetonitrile to obtain a monomer having a cyano group at the terminal shown in Chemical formula 9 (yield 29.3).
g, yield 71%, purity 99%).

Example (1) Synthesis of side chain type liquid crystal polymer

Embedded image Monomer (21.9 g, 43 mmol) in which the terminal hydroxyl group obtained in Synthesis Example (1) was protected with THP and Synthesis Example (2)
The monomer having a cyano group at the terminal obtained in (26.7)
g, 62 mmol) was added to 900 ml of THF, and the mixture was stirred under reflux under a nitrogen stream to completely dissolve each monomer in THF. Thereto, azobisisobutyronitrile (1.76 g, AIBN in the formula) dissolved in a small amount of THF was added dropwise.
After refluxing for 4 hours, p-toluenesulfonic acid monohydrate (10 g, p-TsOH in the formula) was added, and the mixture was further refluxed for 1 hour. After stopping the heating and returning the reaction solution to room temperature, the reaction solution was dropped into 3.6 liters of methanol to reprecipitate the polymer. The polymer is separated by filtration and methanol / THF
= 3/2 (weight ratio), washed twice with 250 ml of a mixed solvent, dried and dried, and the target side shown in Chemical formula 10 (the chemical formula 10 is described as a block body for convenience) A chain type liquid crystal polymer was obtained (yield 37.5 g, yield 77).
%, Weight average molecular weight 4300).

(2) Preparation of Tilt Oriented Retardation Film A 5% aqueous solution of polyvinyl alcohol (trade name: NH-18, manufactured by Nippon Synthetic Chemical Co., Ltd.) was placed on a glass substrate in a 200% solution.
Spin coating was performed at 0 rpm for 20 seconds, heated at 150 ° C. for 30 minutes, and rubbed to form an alignment film. The tetrachloroethane solution (20% by weight) of the liquid crystal polymer obtained in the above (1) is spin-coated on the alignment film,
Heating was performed at 60 ° C. for 5 minutes to obtain a film in which the liquid crystal polymer was oriented. The thickness of the film in which the liquid crystal polymer was oriented was 2.2 μm.

Comparative Example In Example (2), the monomer having a terminal cyano group obtained in Synthesis Example (2) was polymerized instead of the side chain type liquid crystal polymer obtained in Example (1). A film in which a liquid crystal polymer was oriented was obtained in the same manner as in Example 1 (2) except that the obtained homopolymer was used.

Test Example (Measurement of Retardation) The viewing angle dependence of the retardation of the liquid crystal polymer-oriented films obtained in Examples and Comparative Examples was evaluated. Evaluation,
The inclination of the liquid crystal polymer was calculated by the following equation and used as an index of the inclination. Table 1 shows the evaluation results. The front phase difference is △ nd (0), and the phase difference when tilted ± 30 ° in the slow axis direction is △ nd (+30) and △ nd (−3), respectively.
0).

Slope = (△ nd (−30) − △ nd (+
30)) / △ nd (0) When horizontal orientation is not inclined, inclination = 0.

[0054]

[Table 1]

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C09K 19/38 C09K 19/38 G02B 5/30 G02B 5/30 G02F 1/13 500 G02F 1/13 500 1 / 1335 510 1/1335 510 1/13363 1/13363 // C08L 101: 00 (72) Inventor Kyoko Izumi 1-2-1 Shimohozumi, Ibaraki-shi, Osaka Inside Nitto Denko Corporation (72) Inventor Masahiro Yoshioka 1-1-2 Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation (72) Inventor Shu Mochizuki 1-2-1, Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation F-term (reference) 2H049 BA02 BA04 BA06 BA24 BB03 BB43 BC02 BC22 2H091 FA08X FA08Z FA11X FA11Z FB02 LA19 4F006 AA02 AA19 AA35 AA36 AA39 AA40 AB24 BA00 CA05 DA00 DA04 EA02 4H027 BA13 BD12 BD21 4J100 AL08P AL08Q BA02P BA02Q BA03P BA15P BA15Q BA40Q BC43P BC43Q BC44P CA01 CA04 CA05 DA01 JA39

Claims (7)

[Claims] 1. A side chain type liquid crystal polymer comprising a monomer unit having a liquid crystal side chain, wherein the monomer unit comprises (a) a monomer unit having a hydroxyl group at a terminal. polymer. 2. The monomer unit (a) having a hydroxyl group at a terminal is represented by the general formula (a1): (Wherein, R ¹ represents a hydrogen atom or a methyl group, and X ¹ represents —C
An OO- group or an -OCO- group, m is an integer of 1 to 6,
p and q are each independently 1 or 2 (provided that p + q =
Satisfies ≦ 3. ). The side chain type liquid crystal polymer according to claim 1, which is a monomer unit represented by the formula: 3. The side chain type liquid crystal polymer according to claim 1, wherein (a) the monomer unit having a hydroxyl group at the terminal is contained in an amount of 20 to 50 mol% of the monomer unit having a liquid crystal side chain. 4. A monomer unit having a liquid crystal side chain represented by the general formula (b1): (Wherein, R ² represents a hydrogen atom or a methyl group, and X ² represents —C
An OO- group or an -OCO- group, j is an integer of 1 to 6,
s and t are each independently 1 or 2 (provided that s +
It satisfies t ≦ 3. The side chain type liquid crystal polymer according to any one of claims 1 to 3, which comprises (b) a monomer unit having a cyano group at a terminal represented by (1). 5. The side chain type liquid crystal polymer according to claim 1, which has a weight average molecular weight of 2,000 to 100,000. 6. A film comprising the side chain type liquid crystal polymer according to claim 1, wherein the orientation direction of the side chain type liquid crystal polymer is inclined with respect to the film surface of the film. The retarder used. 7. An elliptically polarizing plate obtained by laminating and integrating the retardation plate according to claim 6 with a polarizing plate.