JP2006276573A - Method of manufacturing resin for rotary optical element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a resin for a rotary optical element which does not require highly technical processing or operation such as crystallization adjustment and polishing processing for precision improvement, can form an optical rotation face of a large area, and has uniform optical rotation, to provide a resin for the element obtained by the method, and to provide an optics element made of the resin. <P>SOLUTION: The method of manufacturing the optical rotation optics element resin which orients an optically active polymer including a compression fluid (A) under a super critical pressure and super critical temperature of the fluid (A), the resin is obtained according to the manufacturing method, and the optical rotation optics element comprises the resin. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing a resin for an optical rotatory optical element in which an optically active polymer containing a compressive fluid is oriented, and an optical element using the same.

As an optical rotator for rotating the direction of linearly polarized light and elliptically polarized light such as a half-wave plate, an optical rotatory crystal plate and a phase difference plate, an optical rotator such as quartz or a birefringent crystal such as calcite (Patent Document 1), an optically active polymer (Patent Document 2), and the like are known.
JP-A-9-90123 JP 2002-296416 A

However, the method using crystals requires high technology and complicated operations for crystal adjustment and polishing for improving accuracy, and has a problem that it is difficult to form a large area. Moreover, the thing which consists of an optically active polymer has the fault that uniform orientation of a polymer is difficult and sufficient optical rotation cannot be obtained. That is, an object of the present invention is to provide a resin for an optical rotatory optical element capable of forming a large-area optical rotatory surface without requiring crystal adjustment or polishing treatment.

  As a result of intensive studies to solve the above problems, the present inventors have reached the present invention. That is, the present invention provides a method for producing a resin for an optical rotatory optical element, comprising orienting an optically active polymer containing a compressive fluid (A) under the supercritical pressure and supercritical temperature of (A); An optical rotatory optical element resin produced by the production method; an optical rotatory optical element comprising the resin.

In the method for producing a resin for optical rotatory optical elements of the present invention, an optically active polymer that is difficult to be oriented is melted in a compressive fluid and then molded in an atmosphere within the supercritical temperature and supercritical pressure range of the compressive fluid. By doing so, there is an effect that the orientation becomes easy. Therefore, the resin for optical rotatory optical elements can be easily manufactured by using the manufacturing method of the present invention.

  The production method of the present invention is a method for producing a resin for an optical rotatory optical element, wherein the optically active polymer (B) is oriented in an environment of a supercritical pressure / supercritical temperature region of the compressive fluid (A). is there.

  In the production method of the present invention, the optically active polymer (B) is melted in the compressive fluid (A). Next, (B) plasticized by (A) is extruded onto a support such as a film under the critical pressure / critical temperature of a compressive fluid, and oriented by gradually lowering the pressure and temperature (B ) Is formed on a support in the form of a sheet or film, and a resin sheet or film for an optical rotatory optical element can be produced.

  In the production method of the present invention, a film- or sheet-form optical rotatory optical element resin can be easily produced, and the area and thickness thereof can be appropriately adjusted as necessary. For example, the fluidity of the plasticized (B) can be adjusted by adjusting the temperature during orientation by adjusting the molecular weight and Tg of the optically active polymer (B), and the film thickness at the time of film formation can be adjusted.

  In the production method of the present invention, examples of the compressible fluid (A) include carbon dioxide (31.0, 7.4), methane (-82.5, 4.6), and ethane (31.1, 4.9). ), Propane (96.7, 4.2), hexane (234.2, 3.0), methanol (239.4, 8.2), ethanol (240.7, 6.1), water (374. 2, 22.1), etc., and fluids at temperatures and pressures above the critical point. In addition, the inside of a parenthesis is a critical temperature (degreeC) and a critical pressure (MPa) in order. A supercritical fluid is defined as a non-condensable fluid that exceeds the gas-liquid critical temperature and pressure inherent to the substance. The thermal motion of the molecule is intense because it exceeds the critical temperature, and the density can be continuously changed by changing the pressure from a dilute state close to the ideal gas to a high-density state corresponding to the liquid. .

The compressible fluid (A) in the present invention is preferably used as a supercritical fluid.
Of these, carbon dioxide, methane, and ethane are preferable from the viewpoint of ease of handling, and carbon dioxide is more preferable.

  In the production method of the present invention, the optically active polymer (B) may be obtained by separately polymerizing in advance, or the optically active monomer (m) having specific rotation in (A). (B) obtained by polymerizing) can be used as it is.

  When the optically active monomer (m) having specific rotation is polymerized in the compressive fluid (A), the amount of (A) used is 10 to 1000 with respect to 100 parts by weight of the optically active polymer (B). Part by weight is preferable, more preferably 30 to 800 parts by weight, and particularly preferably 50 to 500 parts by weight.

As the optically active monomer (m), α-alkyl (alkyl group having 1 to 4 carbon atoms) -α-hydroxycarboxylic acid, α-hydrocarbyl (hydrocarbyl group having 1 to 12 carbon atoms) -α-amino acid , Α-hydrocarbyl (hydrocarbyl group having 1 to 8 carbon atoms) methacrylate, cyclic ester having asymmetric carbon (total carbon number of 3 to 6), α-alkylethylene oxide (total carbon number of 6 to 9), α-alkylethylene sulfide (total carbon number 6 to 9) and the like can be mentioned.
The optically active polymer (B) can be produced, for example, by homopolymerizing the optically active monomer (m) exhibiting specific rotation.

Examples of the alkyl group having 1 to 4 carbon atoms in the α-alkyl-α-hydroxycarboxylic acid include a methyl group, an ethyl group, and an isopropyl group, and specific examples thereof include L-lactic acid and D-lactic acid.
The optically active polymer (B) can be produced, for example, by homopolymerizing the optically active monomer (m) exhibiting specific rotation.

The hydrocarbyl group having 1 to 12 carbon atoms in the α-hydrocarbyl-α-amino acid may be any of an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and an aralkyl group, such as a methyl group, an ethyl group, and a phenyl group. Group, benzyl group, α-methylbenzyl and the like, and specific examples include γ-benzylglutamic acid and γ-methylglutamic acid.
The optically active polymer (B) can be produced, for example, by homopolymerizing the optically active monomer (m) exhibiting specific rotation.

Examples of the hydrocarbyl group in α-hydrocarbyl methacrylate include those described above, and specific examples include α-methylbenzyl methacrylate and methyl methacrylate.
The optically active polymer (B) can be produced, for example, by homopolymerizing the optically active monomer (m) exhibiting specific rotation.

Specific examples of the cyclic ester having an asymmetric carbon include L-lactide, D-lactide, α-methyl-α-ethyl-β-propiolactone, and β- (1,1-dichloropropyl) -β-pro. Piolactone is mentioned.
The optically active polymer (B) can be produced, for example, by homopolymerizing the optically active monomer (m) exhibiting specific rotation.

Examples of the alkyl group in α-alkylethylene oxide include those described above, and specific examples thereof include t-butylethylene oxide.
The optically active polymer (B) can be produced, for example, by homopolymerizing the optically active monomer (m) exhibiting specific rotation.

Examples of the alkyl group in the α-alkylethylene sulfide include those described above, and specific examples thereof include t-butylethylene sulfide.

The optically active polymer (B) may be one or more polymers of the optically active monomer (m), or may be a copolymer of the optically active monomer and the non-optically active monomer (n).
In the case of a copolymer with the non-optically active monomer (n), an optically active unit can be easily formed, so that it is preferably a block copolymer containing one type of (m) homopolymer moiety. The degree of polymerization of the homopolymer part (m) in the homopolymer and the block copolymer is preferably from 10 to 100,000, more preferably from 20 to 50,000, particularly preferably from 50 to 50,000, from the viewpoint of easy orientation. 10,000.
Generally, it is known that a helical polymer is formed by homopolymerizing an optically active monomer having an optical purity of 100%. The structure of the helical polymer unit is confirmed by an X-ray crystal structure analyzer [manufactured by Rigaku Corporation]. , AFC7R, etc.] can be used to distinguish left-handed and right-handed.

The optically active polymer (B) may be a copolymer of optical isomers. In this case, the optical isomer content (wt%) is 0 based on the weight of the optically active polymer from the viewpoint of optical properties. 0.1 to 10 is preferable, 0.2 to 5 is more preferable, and 0.3 to 3 is particularly preferable.

  As the optically active polymer (B), polylactic acid is preferable from the viewpoint of optical properties, and polylactic acid L is more preferable.

The other monomer (n) forming the copolymer is not particularly limited. For example, a copolymerizable monomer described in JP-A-2002-296416 [for example, hydroxycarboxylic acid (glycolic acid, dimethyl glycolic acid, etc.) ), Polyhydric alcohols (ethylene glycol, 1,2-propanediol, etc.) and the like.

  The polymerization reaction mode for producing the optically active polymer (B) may be any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc., but stereoregular polymerization is easy. In view of the above, ring-opening polymerization of cyclic monomers having asymmetric carbon, α-alkylethylene oxide, α-alkylethylene sulfide and the like, and dehydration condensation of hydroxycarboxylic acid are preferable.

  As a catalyst used for ring-opening polymerization and dehydration condensation, a known catalyst is used, and can be appropriately selected in consideration of reactivity and selectivity. For example, base catalysts include hydroxides of alkali metals (Li, Na, K, etc.), alcoholates of alkali metals (Li, Na, K, etc.), and alkylamines (monoalkylamines, dialkylamines, trialkylamines). Examples of acid catalysts include Lewis acid catalysts such as halides and alkoxides of metals (Al, Sb, B, Be, P, Fe, Zn, Ti, Zr, etc.), inorganic acids (HCl, HBr, H 2 SO 4). , HClO4, etc.) and organic acids (acetic acid, oxalic acid, etc.), and two or more of them can be used in combination. The amount of the polymerization catalyst used is preferably 0.001 to 5% by weight based on the weight of all monomers to be reacted.

  In the present invention, the weight average molecular weight of the optically active polymer (B) is preferably 5,000 to 10,000,000, more preferably 10,000 to 1,000,000, particularly from the viewpoint of easy orientation. Preferably it is 20,000-500,000.

The temperature (° C.) for orienting the optically active polymer in the compressive fluid is in the supercritical region temperature range of the compressive fluid (A), and is preferably 31 to 250 in the case of carbon dioxide from the viewpoint of operability, more preferably 50 to 230, particularly preferably 70 to 220 ° C.
The pressure (MPa) at the time of orientation is in the range of the supercritical region pressure of (A). From the viewpoint of operability, it is preferably 7 to 70, more preferably 8 to 50, particularly preferably 9 to 30 in the case of carbon dioxide. is there.
The treatment time (time) may be adjusted as necessary, but is preferably 0.1 to 10, more preferably 0.3 to 8, and particularly preferably 0.5 to 5 from the viewpoint of productivity.

In the production method of the present invention, if necessary, the optically active polymer in the compressive fluid may be oriented in a magnetic field. When a magnetic field is used, the magnetic field can be obtained from a permanent magnet, an electromagnet, a superconducting magnet, or the like.
The magnetic flux density (Tesla) may be adjusted as necessary, but is preferably 0.01 to 30, more preferably 0.1 to 20, and particularly preferably 1 to 15.

Additives can be added for the purpose of improving the orientation of the optically active polymer. Specific examples of the additive include, for example, ferromagnetic materials (for example, metals (α-Fe, γ-Co, etc.), spinel type ferrites (Fe3O4, γ-Fe2O3, etc.)) described in JP-A No. 2002-296416, or the like. Examples thereof include liquid crystal compounds (cholesteryl bromide, cholesteryl-n-hexyl ether, etc.).
The composition ratio (% by weight) of the additive to be added is not particularly limited, but is preferably 0.001 to 100, more preferably 0.01 to 50, and particularly preferably 0.1 based on the weight of the optically active polymer. -10.

The optical rotatory optical element of the present invention is produced by orienting an optically active polymer (B) containing a compressible fluid (A) under the critical pressure and critical temperature of (A).

  By processing the oriented optically active polymer (B), it can be used as an optical element. The shape of the optical element is not particularly limited, but is usually a molded product such as a rod, a film, a sheet, a fiber, a filament, a strand, or the like.

For example, when processing into a film shape, a method of removing a compressive fluid after extrusion molding of an optically active polymer containing a compressive fluid by an injection molding method can be applied.
The molded optically active resin is cut according to the shape and size of the target optical element and used for an optical rotatory optical element.

  The optical element of the present invention has high optical rotation because the asymmetric carbon of the main chain is oriented. When used as an optical rotatory optical element, the optical rotatory power (° / 1 mm) is preferably from 10 to 10,000, more preferably from 50 to 8000, and particularly preferably from 100 to 6000, from the viewpoint of optical properties. Optical rotatory power is a film created, and a refractive index ellipse described in an ordinary polarimeter (SEPA-200, manufactured by HORIBA, Ltd.) or a reference (Functional Materials Vol. 20, No. 7, pages 5 to 11). It can be measured using a body measuring device or the like.

EXAMPLES Next, the present invention will be specifically described with reference to examples, but the present invention is not limited to the examples without departing from the gist of the present invention. Unless otherwise specified, “part” means “part by weight” and “%” means “% by weight”.
[Example 1]
A reactor equipped with a stirrer, a circulation tank, and a temperature measuring apparatus, and charged with 100 parts of L-lactide and 0.01 part of stannous octylate in a reaction tank that can be set up to a pressure of 70 MPa and a temperature of 290 ° C., 5 mmHg , Dried at 30 ° C. for 2 hours, charged with 30 parts of carbon dioxide at a pressure of 10 MPa and 200 ° C., and reacted for 3 hours to obtain an optically active polymer.
After completion of the reaction, supercritical carbon dioxide was continuously supplied at a pressure of 10 MPa and 80 ° C. at a flow rate of 50 parts / minute, and unreacted substances and impurities contained in the optically active polymer were extracted for 1 hour. By extruding the optically active polymer at a temperature of 80 ° C. onto a 15 mm diameter fused silica (manufactured by CVI Laser Corporation), the supercritical carbon dioxide was removed by returning the pressure to normal pressure over 1 hour, An optical rotatory film (1) having a thickness of 50 μm was obtained.

[Example 2]
An optical rotatory film (2) having a thickness of 50 μm was obtained in the same manner as in Example 1 except that the temperature during film formation was changed from 80 ° C. to 50 ° C.

[Example 3]
An optical rotatory film (3) having a thickness of 50 μm was obtained in the same manner as in Example 1 except that the temperature during film formation was changed from 80 ° C. to 150 ° C.

[Example 4]
An optical rotatory film (4) having a thickness of 50 μm was obtained in the same manner as in Example 1 except that the pressure during film formation was changed from 10 MPa to 20 MPa.

[Example 5]
An optical rotatory film (5) having a thickness of 50 μm was obtained in the same manner as in Example 1 except that the pressure during film formation was changed from 10 MPa to 30 MPa.

[Example 6]
An optical rotation film (6) having a thickness of 50 μm was obtained in the same manner as in Example 1 except that 100 parts of L-lactide was replaced with 100 parts of D-lactide.

[Example 7]
When extruding onto a fused silica, the same procedure as in Example 1 was conducted except that two 1 Tesla permanent magnets (interval of 10 mm) were placed at the upper and lower positions sandwiching the molded optically active polymer and the fused silica. An optical rotation film (7) having a thickness of 50 μm was obtained.

[Comparative Example 1]
A reactor equipped with a stirrer, a circulation tank, and a temperature measuring device, in which a pressure in the tank of 70 MPa and a temperature in the tank of 290 ° C. can be set, is charged with 100 parts of L-lactide and 0.01 part of stannous octylate, The mixture was dried at 5 mmHg and 30 ° C. for 2 hours, and reacted for 3 hours with stirring.
After completion of the reaction, unreacted substances were removed at 5 mmHg and 200 ° C. for 1 hour.
An optical rotation film (8) with a thickness of 50 μm was obtained by dissolving in 1000 parts of chloroform and casting on Fused Silica.

[Comparative Example 2]
When casting on Fused Silica, the same procedure as in Comparative Example 1 was performed except that two 1 Tesla permanent magnets (interval of 10 mm) were placed at the upper and lower positions sandwiching the coated optically active polymer solution and Fused Silica. An optical rotation film (9) having a thickness of 50 μm was obtained.

<Optical rotation evaluation>
The obtained optical rotatory films (1) to (9) were measured at 10 points using a refractive index ellipsoid measuring apparatus, and the average value of the results is shown in Table 1.

From the above evaluation results, it can be seen that the film obtained by the method for producing an optical rotatory optical element of the present invention has very high optical rotatory power as compared with the comparative example.

Since the optical element of the present invention has high optical rotation and excellent optical characteristics, it can be used as a light modulation element.
Also, in the fields of optical communication systems, optical switching systems, and optical measurement systems, optical rotators, wave plates, polarizing plates, optical deflectors, retardation plates, waveguides, lenses, optical fibers, optical fiber coating materials, light emitting elements, light Modulation element, optical amplification element, optical switch, optical shutter, dimmer, dimming panel, magneto-optical storage element, optical memory, recording medium such as hologram, optical arithmetic element, barcode, solar cell, photodetector, semiconductor It can be used for display materials such as laser, solid-state laser, LED, EL, spatial light modulator, wavelength conversion element, optical isolator, photorefractive, PSHB, liquid crystal panel, and head-up display.

Claims (9)

  A method for producing a resin for an optical rotatory optical element, comprising orienting an optically active polymer (B) containing a compressive fluid (A) under the supercritical pressure and supercritical temperature of the (A).   The production method according to claim 1, wherein the optically active polymer (B) is a polymer obtained by polymerizing a monomer containing the optically active monomer (m) in a compressive fluid.   The production method according to claim 1 or 2, wherein (A) is carbon dioxide in a supercritical state.   The production method according to claim 2 or 3, wherein (B) is a polylactic acid L-form or a polylactic acid D-form.   The manufacturing method according to any one of claims 1 to 4, wherein the optically active polymer (B) is oriented by applying a magnetic field having a magnetic flux density of 0.01 to 30 Tesla.   The manufacturing method according to any one of claims 1 to 5, wherein the pressure during orientation is 7 to 70 MPa and the temperature is 31 to 250 ° C.   A resin for optical rotatory optical elements produced by the production method according to claim 1.   An optical rotatory optical element comprising the resin according to claim 7. The optical element according to claim 8, wherein the optical rotation is 10 to 10000 ° / mm.