KR100317294B1 - Polymers for storing an information, thin film coated with said polymers, apparatus and method for storing an information using said thin film - Google Patents

Abstract

The present invention relates to a polymer compound for storing information sensitive to a laser light source, a recording thin film coated with the compound, an information storage device using the recording thin film, and an information storage method, and more particularly, to a photoresponsive organic dye. Reversible and optical digital information recording and reading device comprising a polymer compound for information storage, a thin film coated with the compound, and the thin film in which disperse red 1 is bound to two side chains per repeating unit structure, and It relates to the method used.

Description

Polymer compound for information storage, thin film coated thereon, information storage device using the thin film and method thereof {POLYMERS FOR STORING AN INFORMATION, THIN FILM COATED WITH SAID POLYMERS, APPARATUS AND METHOD FOR STORING AN INFORMATION USING SAID THIN FILM}

The present invention relates to a polymer compound for storing information sensitive to a laser light source, a recording thin film coated with the polymer compound, an information storage device using the recording thin film, and an information storage method, and more particularly, to a photoresponsive organic material. Reversible and optical digital information recording and reading apparatus comprising a polymer compound for storing information in which a dye disperse red 1 is bonded to two side chains per repeating unit structure, the thin film coated with the compound, and the thin film And a method of using the same.

In general, the optical information storage method uses an information storage medium composed of a short wavelength laser and an organic dye-based compound sensitive to the laser, thereby enabling high-density information storage. In this case, since the organic dye-based compounds are easy to convert the structure and excellent processability for manufacturing a thin film, the reversible and optical information storage method using the organic dye-based compound or optical functional polymers having these compounds as a substituent as an information recording medium is known in the United States. Patent Nos. 5,262,081, 5,445,853, 5,296,321, 4,666,819, 5,384,221, German Patent No. 3,623,395, British Patent GB 2.146787A, Japanese Patent Application Laid-Open No. 1-294791, and the like. come.

The principle of the reversible information storage method capable of information recording-erasing-reading-rewriting is as follows. When the laser for information recording is irradiated to an information recording medium containing an organic dye compound, the organic dye compounds are changed in color, birefringence and phase transition depending on their molecular structure. Amorphous, or isotropic ↔ anisotropic phase).

The organic dye compounds that can be used in the above known techniques include cyanine, phthalocyanine, squarilium, dithiol metal complex salts, quinones, spiro Numerous dyes have been reported, such as the pyranpyran or azobenzene series.

Looking at the molecular structure of the compounds, the compounds contain different polar groups inducing a dipole moment in the molecular structure. Therefore, when polarized light having a specific wavelength is irradiated onto an information storage medium made of a material containing the compound, molecules of the material are irradiated by the mutual attraction of the dipole moments induced in the polar group. perpendicular to the polarization). From the oriented molecules, desired information can be recorded on the information storage medium by using the above-described three principles of optical property change.

Looking at the above known techniques in more detail, the organic dye-based compounds used as information storage medium absorbs ultraviolet or infrared light having a wavelength between 300 and 800 nm depending on the structure of the polar molecules introduced . Therefore, for the development of the information storage element, it is also important to select a light source that determines the wavelength of light together with the information recording medium causing the optical property change.

Generally, the light source used in the optical information storage method is Ga / As, He-Ne, Ar ion, Nd / YAG, or He-Cd having a wavelength of 780, 630, 488, 514, 360 or 325 nm. The same lasers have been known mainly.

However, in a compact disc (CD) or a laser disc (LD) for applying optical information storage media, only a Ga / As having a wavelength of 780 nm and a He-Ne laser having a wavelength of 630 nm of the light sources drive the disc. It is commercially available as a compact light source for a drive.

However, since the light sources emit relatively long infrared light having a wavelength of 600 nm or more, when used as a recording light source of an optical information storage device, the information storage density is reduced.

That is, when a long wavelength polarized recording light source is irradiated on a thin film made of a material containing an organic dye-based compound that causes optical property change in the information recording step, light is irradiated than when using a short wavelength recording light source. The irradiation area of the recording medium is widened. Therefore, when the short wavelength (520 nm or less) argon ion laser in the commercialization stage is used as a recording light source, the area of the recording medium can be reduced, so that the density of information recording per unit area can be increased.

The present applicant has developed high molecular compounds having an azo benzene-based organic dye compound in the side chain in order to improve the storage density of the information described above. In addition, the polymer compounds are sensitive to the recording light having a short wavelength of 300 to 400nm because the azo benzene series is substituted in the side chain.

Therefore, the applicants have been patented by Korean Patent No. 77801 (filed February 27, 1991) by investigating the applicability of the polymer compound to reversible and optical information storage media. 40216 (filed Aug. 22, 1997).

Looking at the technology in more detail, the azobenzene compound is coated with a polymer compound substituted in the side chain on a substrate to produce a thin film, and the high-density information is recorded with excellent resolution by irradiating the ultraviolet light of low power to the prepared thin film The recorded information can be erased and then rewritten.

Another feature of the above invention is that the azobenzene compound is bonded to the side chain, two per repeating structure of the polymer compound.

The media have a resolution and recording speed of information (hundreds of nanoseconds) than conventional ones used in US Pat. No. 5,173,381, German Pat. No. 3,623,395, US Pat. No. 4,837,745 and Japanese Patent Laid-Open No. 63-87626. Showed much faster.

The advantage of the pulsed laser is not only based on the molecular structure of the polymer compounds used, but also a Nd / YAG pulsed laser that emits short-wave ultraviolet (365 nm) below 10 nanoseconds as recording light. This enables high-density information to be recorded at hundreds of nanoseconds.

However, such a short wavelength pulse laser has a disadvantage that it is expensive and bulky due to the use of an inorganic single crystal as a material of light source oscillation, which makes it difficult to construct a small optical information storage device.

Therefore, in recent years, research has been actively conducted to apply a small-sized argon-ion laser as a recording light source for information storage, although the wavelength is slightly longer than the used ultraviolet rays, and the wavelength can be modulated.

The present invention has been made to solve the above problems of the prior art, and provides a polymer compound for information storage, and provides a thin film coated thereon as a recording thin film.

The present invention also provides an information storage device and an information storage method for recording and reading information on the recording thin film.

1 is a reversible and optical information storage device according to the present invention;

2 is a digital information image obtained by reading a digital polarized light of 1 to 5 mW intensity linearly polarized argon laser to a recording thin film coated with a polymer compound according to the present invention for 10 microseconds and reading the digital information recorded by an optical polarized light microscope;

FIG. 3 shows the recording of the reading light SDL 800 for recording information with an argon ion laser light source of 8 mW / cm 2 intensity on a polymer prepared by the polymerization of p-xylene and malonic acid ester in one embodiment of the present invention. It is a graph showing the result of measuring the penetration strength;

4 is a graph showing stability with temperature of information stored in the polymer-coated information recording thin film used in FIG. 3;

FIG. 5 shows an analog information image obtained by reading an optically polarized microscope for analog information stored by cooling the glass transition temperature below the glass transition temperature of the recording thin film after irradiating argon ion laser polarization with 10 mW / cm 2 intensity for 5 minutes in one embodiment of the present invention. Is a schematic diagram of; And

FIG. 6 is a graph showing information reading on a recording thin film coated with a polymer prepared from polymerization of the polymer of formula 1 and polyvinylcarbazole in the present invention.

Detailed description of the symbols for the main parts of the drawings

1: Argon (+) ion laser and driver 9: Photodiode

2: IR laser and driver 10: digital voltmeter

3: Convex lens 1 11: Mirror 1

4: Block lens 2 12: Wave plate

5: polarizing prism 13: variable attenuator

6: Slide glass coated with polymer compound

7: Analyzer 14: Mirror 2

8: Convex lens 3 15: polarization prism

16: Computer

The present invention provides a polymer compound for storing information, wherein Disperse Red 1 of the following structural formula is bonded to the side chain of the polymer repeating unit two by two.

Preferably the present invention is a polymer compound for information storage represented by the formula 1:

To provide

Wherein n is an integer, m is 2, 4, 6, 8 or 10, and R is

The weight average molecular weight of the polymer compound is 2,000 to 15,000.

In addition, the present invention is a polymer compound for information storage represented by the following Structural Formula 2:

Structural Formula 2

To provide

Wherein n is an integer;

remind

Represents that two -CH ₂ -bonded to the benzene group are bonded to the ortho, meta, or para position;

R is

Is;

The weight average molecular weight of the high molecular compound is about 2,000 to 15,000.

Meanwhile, the present invention is a polymer compound for information storage represented by the following Structural Formula 3:

To provide

Wherein n is an integer;

R is

Is;

The weight average molecular weight of the high molecular compound is about 2,000 to 15,000.

On the other hand, the present invention is a polymer compound for information storage represented by the following structural formula 4:

To provide

Wherein R is

Is;

X is 3 to 97% in molar ratio;

Y is from 97 to 3% in molar ratio;

The weight average molecular weight of the high molecular compound is about 2,000 to 15,000.

Meanwhile, the polymer compound for storing information of Structural Formulas 1, 2 and 3 according to the present invention preferably has a weight average molecular weight of about 3,000 to 10,000.

In addition, in the polymer compound for storing information of Structural Formula 4, X is preferably 5% to 30% in molar ratio and Y is preferably 95% to 70% in molar ratio.

In another aspect, the present invention is a blend for storing information made by mixing any one of the polymer compounds of the above-mentioned information storage polymer compounds of Formulas 1 to 4 and polymethyl methacrylate or polyvinylcarbazole in a tetrahydrofuran (THF) solvent (blend) copolymers.

The blend copolymer may include 5 to 30% by weight of any one of the polymer compound of the polymer compound for storing information of Structural Formulas 1 to 4.

The present invention also provides an argon laser light source 2, a polarizing plate 15 to which a blue laser irradiated from the light source is incident, an optical attenuator 13 to which a blue laser passing through the polarizing plate 15 is incident, and the light A wave plate 12 into which the polarized light passing through the attenuator 13 is incident and a recording thin film 6 coated with the polymer compound for information storage according to the present invention, which is located on a path of the polarized light passing through the wave plate. Provided is a reversible and optical information recording apparatus configured.

At this time, the recording thin film (a) dissolving the polymer compound in an organic solvent to prepare a thin film; (b) heating the thin film to a melting temperature inherent to the polymer compound; (c) cooling the heated thin film to a glass transition temperature (T _g ) or less to fix an isotropic state of the thin film polymer.

The argon laser light source also emits short wavelengths between 400 and 520 nm.

The reversible and optical information recording apparatus further comprises an acousto-optic modulator between the optical attenuator and the wave plate to shield the transmission of argon laser polarization to achieve an information recording rate of up to 1 microsecond.

A light source attenuator may be further included, wherein the wave plate has a wavelength of λ / 2.

On the other hand, the present invention provides an IR laser light source (2), an optical lens (3, 4) to which light irradiated therefrom, a first polarizing plate (5) to which light passing through the optical lens is incident, and A recording thin film 6 coated with a polymer compound according to the present invention, which is located on a path of light passing through the first polarizing plate 5, and is located on a path passing through the recording thin film 6, wherein the first polarizing plate A second polarizing plate (7) having a polarization axis perpendicular to the polarization axis of (5) and an output device for inputting light passing through the second polarizing plate (7) to output the information recorded on the recording thin film (6). It provides a reversible, optical information reading apparatus.

The recording thin film is preferably the same as the recording thin film manufacturing method of the information recording apparatus.

As the IR laser light source, a light source of Ga / As having a wavelength of 847 nm or He-Ne having a wavelength of 633 nm is preferable.

The recording thin film is positioned by forming an angle of (1 + n) π / 4 (where n is 0, 2, 4 or 6) with the polarization axes of the first and second polarizing plates, respectively.

The output device is preferably composed of a digital voltmeter 10 for sensing the intensity of light as the intensity of the current, and a computer 16 for processing the intensity of the sensed current by time to record information and to read in real time. have.

The present invention also provides a reversible and optical information reading apparatus manufactured by the method for manufacturing the reversible and optical information reading apparatus.

The present invention (a) applying a polymer compound according to the invention on a thin film; (b) forming the recording thin film by heating the coated polymer compound above the melting temperature of the used compound and isotropically arranging the same, followed by quenching below the glass transition temperature (T _g ) of the polymer compound; (c) recording digital information on the recording thin film by using polarized light which is irradiated from an argon laser light source and sequentially passed through a first polarizing plate, a light attenuator, and a wave plate; (d) passing the polarized light which is irradiated from the IR laser light source to the recording thin film on which the digital information is recorded and sequentially passed through the optical lens and the second polarizing plate, and then passing the polarized light perpendicular to the polarizing axis of the second polarizing plate Reading digital information by passing it through a third polarizing plate and inputting it to an output device; (e) erasing the recorded and read digital information from the recording thin film; And (f) rewriting and rereading the information by repeating steps (c) and (d) on the recording thin film in which the digital information has been erased.

On the other hand the present invention (a) applying a polymer compound according to the invention on a thin film; (b) forming the recording thin film by heating the coated polymer compound above the melting temperature of the used compound and isotropically arranging the same, followed by quenching below the glass transition temperature (T _g ) of the polymer compound; (c) a photomask having a fine pattern recorded thereon is placed on the recording thin film, and then analog information is recorded on the recording thin film by passing polarized light sequentially irradiated from an argon laser light source and passing through the first polarizing plate, the optical attenuator, and the wave plate. Doing; (d) passing the polarized light which is irradiated from the IR laser light source to the recording thin film on which the analog information is recorded and sequentially passed through the optical lens and the second polarizing plate, and then passing the polarized light perpendicular to the polarizing axis of the second polarizing plate Reading analog information by passing it through a third polarizing plate and inputting it to an output device; (e) erasing the recorded and read analog information from a recording thin film; And (f) rewriting and rereading the information by repeating steps (c) and (d) on the recording thin film from which the information has been erased. do.

In this digital or analog information storage method, the recording thin film forms an angle of (1 + n) π / 4 ° (where n is 0, 2, 4 or 6) with the polarization axes of the second and third polarizing plates, respectively. Is located.

In addition, the analog information reading step is preferably read by using a low-power optical polarizing microscope is attached to the second polarizing plate and the third polarizing plate perpendicularly intersecting the analog information recorded on the thin film.

In the digital or analog information storage method, the information erasing step of (f) records circularly polarized light transmitted by the wave plate having a wavelength of λ / 4 when the wave plate of (c) has a wavelength of λ / 2. It is preferable that the information is erased from the recording thin film by passing through the thin film, or the digital information is erased from the recording thin film by heating the recording thin film to a temperature higher than the melting temperature of the polymer compound used.

The polymer compound for storing information of Structural Formula 1 may be selected from the group consisting of the malonic ester monomer of the following formula and two bromines substituted with the first carbon and the mth carbon, respectively, C _m H _2m Br ₂ (m is 2, 4, 6, 8, or 10 ) Can be prepared by polymerizing.

R is

to be.

The polymer compound for storing information of Structural Formula 2 may be prepared by polymerizing a malonic ester monomer of the following Structural Formula and two bromine-substituted styrenes.

R is

to be.

The compound of formula 3 can be prepared from the polymerization of silicate ester monomer and the polymer compound for storing information of formula 4 can be prepared by polymerizing methyl methacrylate (MMA) with the silicate ester monomer of the following formula.

R is

to be.

In addition, the glass transition temperature (T _g ) of the polymer compounds according to the present invention is shown between about 20 to 100 ℃.

The maximum absorption wavelength of the monomers and polymers used in the polymer compound of the present invention has a value between 450 and 500 nm. Therefore, the polymer compound may absorb the blue light emitted by the argon ion laser with the maximum efficiency, thereby causing the optical property change such as birefringence in the blue light at the highest speed.

In addition, when the polymer compound having two -CH ₂ -groups in the benzene group and the polymer compound having the structural formula 4 and the polymer compound having the structural formula 4 are used as the recording thin films, the recorded information does not change even at an external temperature of 80 ° C. Showed very excellent information storage stability.

The polymer compounds according to the present invention have a weight ratio of 60% to 80% of the R group to the repeating units of the polymer. In the techniques of US Pat. Nos. 4,551,819, 5,024,784, 5,173,381, German Patent No. 3,623,395 and Japanese Patent Laid-Open No. 63-87626, the weight ratio of organic dyes to repeating units of the polymer is between 15% and 40%. Appears. This indicates that the polymers of the present invention contain more groups with high concentrations of optical properties than the polymers used in the known art.

The polymer, in turn, is capable of exhibiting a fast microsecond information recording rate which has not been reached in conventional technologies and also has the property of excellent stability of stored information.

As described above, the information recording apparatus and the information reading apparatus of the present invention using the polymer compound have improved information recording speed and information storage stability as compared with the conventional apparatus.

Hereinafter, a reversible optical information storage method using an information recording thin film coated with a polymer compound and an optical device according to the present invention will be described in detail.

Digital Information Storage

According to the present invention, after disperse red 1 containing azobenzene group is coated on a glass plate with a polymer bound to two side chains, the glass plate coated with the polymer is heated to a melting temperature (T _m ) or higher of the polymer used, and then glass The film was quenched below the transition temperature T _g to obtain a film such as the recording thin film 6 of FIG. 1, in which molecules were fixed in an disordered state, that is, in an isotropic state.

The film was irradiated with blue polarized light having a desired intensity from the argon ion laser shown in the device diagram of FIG. 1 to record digital information, and then cooled to below T _g of the polymer applied to the film to store the information.

At this time, the intensity and irradiation time of the blue light irradiated for recording the digital information depend on the thickness and structure of the polymer thin film coated on the film.

According to the information storage principle of the present invention, when the recording thin film is exposed to polarized light, the portion irradiated with light is uniformly oriented in the isotropic state as the following photoisomerization occurs in the azobenzene group included in the polymer. Is to use the principle.

That is, a stable trans form azobenzene group causes photoisomerization reaction in cis form by the blue polarization irradiated during information recording, and disordered Disperse Red 1 molecules are perpendicular to the polarization direction irradiated with blue polarization. Will be arranged in the direction. (Nature 1991, 351, 49; Makromol. Chem. Rapid Commun., 8, 477 (1987); Applied optics, 23 , 4309 (1984))

More specifically, Disperse 1 molecules arranged in an isotropic state in the recording thin film are arranged perpendicular to the direction of polarization when exposed to blue polarization, thereby causing birefringence, while not being exposed to polarization. Molecules do not induce birefringence.

At this time, the information signal value of the information storage portion where the birefringence is induced is "1", and the information signal value of the isotropic portion not exposed to polarization is "0". Digital information is stored from the difference in the values.

The signal of the digital information directly affects the transmittance of the read light when reading the information.

The method of the present invention is the opposite of the conventional thermal recording method (polym. Commun., 24,346 (1983)) and the hologram method (German Patent No. 3,623,395) which cause phase transition from liquid crystal phase to isotropic phase by ultraviolet rays or laser light. Is a technology applied.

In addition, the method was first developed by the present inventors and has already been reported in the above-mentioned Korean Patent No. 77801 and recently published Patent Publication No. 1999-17317.

The polymer compound coated on the film disclosed in the Korean patent or the Korean Industrial Publication, that is, the information recording medium is a polymer compound combined with an organic dye sensitive to ultraviolet rays, and the polymer compound causing the photoreaction by the blue laser developed in the present invention. There is a fundamental difference.

In order to develop a new information storage method, the development of a light source-sensitive material along with the development of an optical device should be a priority.

Reading digital information

The present invention can read information stored by the digital information reading device of the present invention shown in the optical device diagram of FIG.

That is, a thin film in which information is stored is inserted between two orthogonal polarizers and irradiated with an IR laser. In this case, the information storage portion exposed to the blue polarized light causes birefringence to maximize the transmittance of the irradiated read light. On the other hand, since the birefringence is not induced in the part not exposed to polarized light, the transmittance becomes "0".

When the polarization axis of the recording light incident upon the information recording is 45 ° with respect to the crossed polarization directions of the two IR polarizers of the information reading device, the IR transmittance of the birefringent-induced information storage portion becomes maximum, whereas the portion not exposed to polarization The IR light is blocked by the two polarizers.

Thus, the difference in the transmittance of the IR laser light resulting from the difference is detected by the photodetector. At this time, the photodetector represents the intensity of light incident on the detector as a voltage change, which is displayed numerically on the digital voltmeter, which is read back through a computer.

As a read light source, a gallium / arsenic (Ga / As) laser having a wavelength of 847 nm or a helium-neon (He-Ne) laser having a wavelength of 635 nm may be used.

On the other hand, since the information is read by the IR transmittance difference between the portion exposed to the blue polarization laser and the portion not exposed, different information can be stored in the same recording layer several times by changing the angle of polarization incident upon the information recording. .

That is, when blue laser polarization is irradiated on an isotropic polymer thin film used as an information recording medium, the disperse 1 molecules exposed to polarization are arranged in a direction perpendicular to the irradiated polarization direction.

Therefore, the following equation is given by measuring the intensity of IR light used by placing a thin film in which birefringence Δn is induced between the polarizing plates perpendicular to each other. In other words,

Where Δn is the birefringence of the information recording thin film, λ is the wavelength of IR light used for reading the information, I ₀ is the intensity of light before passing through the sample, I is the intensity of light passing through the sample, and d is the thickness of the sample and θ. Represents the angle between the axis of the polarizing plate and the optical axis of the polymer chain oriented by argon ion laser polarization.

Therefore, when the angle between the axis of the polarizing plate and the optical axis of the information recording medium is 45 °, 135 °, 225 ° or 315 °, the intensity of the IR transmitted light of the unirradiated and irradiated portions is "0" and sin ² ( π dΔn / λ).

By using this, information on-state, that is, sin ² (πdΔn / λ) and off-state, that is, zero, can be spatially recorded and detected on a medium.

Also, if the angle of blue laser polarization incident on the information recording thin film is arbitrarily changed, different information can be superimposed and stored in the same recording layer.

For example, if the angle of incident polarization is changed by 1 ° with respect to the original angle, θ is changed to (θ + 1) °, and the angles of the two polarizing plates perpendicular to each other at the time of reading the information are on the polarized axis having the changed angle. At 45 °, 135 °, 225 ° or 315 °, the S / N ratio is maximized.

Analog information storage

In the above-described digital information storage method, the information was stored in the same manner as the digital method except that a photomask on which a fine pattern having a line width of 2 to 50 μm was recorded was placed on the recording thin film.

However, in order to obtain a photograph (FIG. 5) having excellent resolution of the analog information recorded on the photomask, it is preferable to record the information under the condition that the intensity of blue light is 5 mW / cm 2 or more and the irradiation time is 5 minutes or more. This condition is necessary because the transmittance of the analog information must be much higher than the intensity of visible light reflected from the outside when the analog information is read using a polarizing microscope.

Reading Analog Information

The analog information recorded as described above may be read by a low power optical polarizing microscope including a polarizing plate perpendicular to each other.

At this time, when the blue laser polarization axis incident upon the information recording is 45 ° with respect to the crossed polarization direction of the optical polarizing microscope, information of excellent resolution with maximum contrast can be obtained.

Erase and rewrite stored information

In FIG. 1, the circularly polarized light can be obtained by rotating the blue laser polarized light that has passed through the optical attenuator 13 into the wave plate 12 of λ / 4 instead of the wave plate of λ / 2 used in the information recording. Can be erased by irradiating the recording thin film 6 on which the information is recorded, or when the thin film is heated above the melting temperature of the polymer used in the thin film, it is arranged vertically by blue laser polarization in the information recording step. Dispersed 1 molecules are rearranged to isotropic state, which can erase information.

Subsequently, after the information thin film is cooled to room temperature, new information can be rewritten by repeatedly using the above-described information recording process on the recording thin film.

The recording thin film coated with the polymer compound for information storage according to the present invention exhibited excellent resolution and storage stability of information which could not be seen in the known art.

Hereinafter, the present invention will be described with reference to Examples. However, the present invention is not limited to these examples.

Example

Preparation of Polymer Compound for Storage of Information According to the Present Invention

Example 1 Preparation of Polymer Compound for Storage of Information of Structural Formula 1

1. Preparation of malonic ester monomer

2.0 g (6.42 × 10 ⁻³ mol) of Disperse Red1 and 70 mL of THF solvent were placed in a three-necked round flask and cooled between 0-5 ° C. To this solution was slowly added THF (5 mL) solution containing 0.22 mL (3.21 x 10 ^-3 mol) of malonyl dichloride through a dropping funnel. The reaction mixture was reacted with stirring for 48 hours. After the reaction, the solvent, THF, was removed by a rotary evaporator. The resulting solid was dissolved in 35 ml of chloroform, washed with distilled water (200 ml × 4 times), and chloroform was removed with a rotary evaporator. The obtained solid was dissolved in a small amount of chloroform, and then chromatographed separation was performed using a mixed solution having a ratio of 5: 1 of chloroform and ethyl acetate as a developing solution to obtain a malonic ester monomer.

The yield was 35%, the melting point was 130 ℃. UV / VIS spectra of the synthesized pure monomers showed a maximum absorption wavelength (λ _max ) at 466 nm.

2. Preparation of polymer compound for storing information of formula 1

1.0 g (1.435 × 10 ⁻³ mol) of the synthesized malonic acid ester monomer, 0.17 g (2.87 × 10 ⁻³ mol) of NaH, and 17 ml of THF were added to a two-necked round flask and stirred at room temperature for 10 minutes. To this solution was slowly added a THF (3 mL) solution containing 0.22 mL (1.435 × 10 ^-3 mol) of 1,6-dibromohexane through a dropping funnel, followed by condensation polymerization at 65 ° C. for 48 hours. Reacted. The reaction solution obtained after polymerization was precipitated in 500 ml of methanol, filtered and dried to obtain the polymer of Structural Formula 1. The polymerization conversion rate of the synthesized red polymer was 60%. The weight average molecular weight of the synthesized polymer was about 5,000. The molecular weight of the polymer can be controlled by varying the polymerization time. The T _g of this polymer was about 30 ° C. and T _m was not measured. When m in the compound of Formula 1 was 6, the maximum absorption wavelength of this polymer was 464 nm.

In addition, polymers for storing information having m of 2, 4, 8, or 10 are 1,2-dibromoethane, 1,4-dibro, instead of 1,6-dibromohexane in the above reaction. Synthesis can be carried out using dibromobutane, 1,8-dibromooctane, or 1,10-dibromodecane.

Structural Formula 1

Example 2 Preparation of Polymer Compound for Storage of Information of Structural Formula 2

In preparing the polymer compound of Structural Formula 1 using the malonic ester monomer in Example 1, instead of 1,6-dibromohexane, α, α'-dibromoparaxylene (dibromo-p-xylene), α, except that 0.38 g (1.435 × 10 ^-3 mol) of α'-dibromo-or-xylene or di, mo'-dibromo-m- ylene Polymerization was carried out in the same manner as 2 in Example 1 to synthesize polymers of Structural Formula 2. Among these polymers, for the homopolymer having the following structure made by polymerization of malonic ester and α, α'-dibromoparaxylene, the weight average molecular weight and T _g were about 5,500 and about 90 ° C., respectively. The maximum absorption wavelength of this polymer was 466 nm.

Example 3 Preparation of Polysilicate Ester of Structural Formula 3

1. Preparation of Silicate Ester Monomers

Dispersed 1 1.13 g (4.14 × 10 ^-3 mol) and 50 ml of methylene chloride were placed in a three-necked round flask and under a nitrogen atmosphere, 0.5 g (2.07 × 10) of 3-Methacryloxypropylmethyldichlorosilane. ^A solution of methylene chloride (10 ml) containing ^-3 mol) was slowly added through a dropping funnel. The reaction mixture was reacted with stirring for 48 hours. After the reaction solution was extracted four times with 200 ml of distilled water, methylene dichloride was removed by a rotary evaporator. The resulting solid was dissolved in a small amount of chloroform and subjected to column chromatography separation using a mixed solution of chloroform and ethyl acetate in a ratio of 7: 1 as a developing solution to obtain a silicate ester monomer. The yield was 40%, the melting point was 88.5 ℃. The maximum absorption wavelength of pure monomer was 482 nm.

2.Preparation of polysilicate polymer for storing information of formula 3

0.4 g (5.01 × 10 ⁻⁴ mol) of the silicate ester monomer synthesized above, 0.012 g (7.3 × 10 ⁻⁵ mol) of AIBN, a radical initiator, and 4 ml of THF were added to an ampoule and freeze-thawing. After removing the oxygen present in the solution, the ampoule was sealed. The solution was subjected to radical polymerization in a 65 ° C. oven for 48 hours. After polymerization, precipitated in 500 ml of methanol, followed by filtration and drying to obtain a polysilicate ester homopolymer of Structural Formula 3. Polymerization conversion, weight average molecular weight, T _g and maximum absorption wavelength of the synthesized polymer were 50%, 6,500, 48 ° C. and 474 nm, respectively. The molecular weight of the polymer can be controlled between 5,000 and 10,000 by adjusting the initiator concentration.

Structural Formula 3

Example 4 Preparation of Polysilicate Ester-PMMA Copolymer

0.4 g (5.01 × 10 ⁻⁴ mol) of silicate ester monomers synthesized in Example 3, 0.017 g (1.0 × 10 ⁻⁴ mol) of AIBN, 0.15 g (1.5 × 10 ⁻³ mol) of conventional monomer MMA, and 5.6 mL of THF Into the ampoule. The initiator AIBN was deoxygenated in the solution and then the ampoule was sealed by freeze-thaw method. The solution was subjected to radical copolymerization at 65 ° C. for 48 hours. After polymerization, precipitated in 500 ml of methanol, filtered, and dried to obtain a red silicate ester-PMMA copolymer having Structural Formula 4. The molar ratio of silicate ester monomer and MMA monomer added in this polymerization experiment was 25% to 75%. In addition, the above-mentioned copolymerization reaction was caused by changing the molar ratio of the silicate monomer and the existing MMA monomer to 75% to 25%, 50% to 50%, or 5% to 95%. As a result, copolymers having different concentration ratios of X to Y could be prepared. The results are shown in the table below.

Results of Polysilicate Ester-PMMA Copolymers of the Invention Co-union Central exchange rate Weight average molecular weight (Mw) Copolymerization reaction condition (II): MMA (molar ratio) Molar ratio of X to Y in copolymer (VI) ^a Tg ^b Structural Formula 4-1 45% 11600 75: 25 57: 43 68.0 ℃ Structural Formula 4-2 65% 13600 50: 50 42: 58 68.1 ℃ Structural Formula 4-3 74% 18700 25: 75 19: 81 76.1 ℃ Structural Formula 4-1 53% 25800 5: 95 3: 97 93.0 ℃

The molar ratio of the silicate ester monomer and MMA monomers present in the copolymer of ^a structural formula 4 was calculated by the H-NMR spectrum analysis.

^b T _g was determined by thermal analysis by DSC.

Information recording and reading results using the information recording and information reading apparatus of the present invention

Example 5 Preparation and Reading Results of Recording Thin Films with Digital Information Recorded

1. Fabrication of recording thin film using information recording apparatus

The poly (malonic acid ester) homopolymer synthesized in Example 2 was dissolved in THF solvent at 4% concentration. The solution was dropped on a glass plate (2 cm × 2 cm), followed by spin coating to prepare a thin film having a thickness of 0.2 μm, and then the solvent was removed under reduced pressure. This was placed on a heating plate and heated at 100 ° C. for 2 minutes, and then cooled to below T _g of the polymer used to obtain a thin film having a fixed isotropic state. The information recording thin film was irradiated with an argon ion laser (Model: INNOVA 400; wavelength: 488 nm) polarization shown in the optical device of FIG. 1 to record digital information. The recorded information was then stored by cooling below the T _g of the polymer compound used. The speed and storage stability of the information recording depended on the intensity of the recording light and the thickness and molecular structure of the polymer thin film used as the recording medium.

2. Result of reading thin film on which digital information manufactured in 1 is recorded

FIG. 2 is an image obtained by optical polarization microscopy of digital information obtained by irradiating a linearly polarized argon ion laser of 1 to 5 GHz intensity on a recording thin film layer coated with the poly (malonic acid ester) polymer for 10 microseconds. )to be. The bright parts in the image represent digital information recorded by birefringence while being arranged perpendicular to the recording polarization.

3 is a basic experiment conducted to investigate a method of reversibly storing digital information (record-read-erase-rewrite). That is, the information is recorded on the recording thin film layer prepared from the poly (malonic acid ester) polymer using an argon ion laser light source (light intensity: 8 mA / cm 2), and the read light (SDL 800) is transmitted to the recorded information. This is an experiment to measure the transmitted intensity. The transmission intensity is recorded in real time as a function of the irradiation time of the recording light. That is, as shown in FIG. 3, when the recording light source is turned on, the polymers in the recording thin film layer are arranged so that the information is recorded (indicated by an increase in the transmission intensity), and then argon ion laser circularly polarized light (described in the erasing and rewriting of stored information). The recorded information is erased. The erased information can be rewritten again by repeating the above-described information recording process. The reversibility of this information shows that it is very stable and uniformly repeated.

In addition, the recorded information may be erased by heating above the melting temperature of the used information recording medium.

4 is a result of investigating the stability according to the temperature of the information stored in the polymer-coated information recording medium in which two -CH ₂ -are bonded to each other in the para position in the formula (2). That is, in order to investigate the storage stability of the information about the temperature, the glass plate coated with the recording thin film was placed in a heating plate made of two aluminum plates kept at a constant temperature, and the transmission intensity of the read light was specified while irradiating the recording light source. As a result, it can be seen that the recorded information is stored stably even at 75 ℃.

This result cannot be achieved with an information storage medium used in the known art so far.

Example 6 Analog to Recording Thin Film Coated with Polysilicate Polymer

How to record and read information

On the recording film coated with the polysilicate ester homopolymer prepared in Example 3, a photomask (line width: 2 to 50 µm) on which analog information was drawn was placed, and the analog information was recorded by irradiating argon ion laser polarization.

FIG. 5 is an analog information image obtained by an optical polarizing microscope of analog information obtained by irradiating argon ion laser polarization having an intensity of 10 μs / cm 2 for 5 minutes and then cooling it below T _g of the recording thin film. Here, the line width of the information indicated by the arrow (?) Was 2 m, and the resolution of the recorded information was very good.

Example 7 Preparation of Blended Polymers and Information Groups of Thin Films Coated with the Polymers

Lock and read

The polymer synthesized in Example 1 and the conventional polymer PVK were dissolved in THF to form a 4% polymer solution, and then coated on a glass plate to prepare an information recording thin film having a thickness of about 0.3 μm. At this time, the weight ratio of the polymer of the formula 1 and PVK was 10% to 90%. Experiments were performed on the thin film in the same manner as in the information recording and reading step of Example 5.

FIG. 6 is a graph showing the results of reading information from a recording thin film coated with a polymer of formula 1 prepared in Example 1 and a blend polymer polymerized with PVK, from which the blend polymer also records the reversible and optical information of the present invention. It can be seen that it can be applied as a medium.

In the above embodiment, as the argon ion laser in the information storage device, a laser having a wavelength of 458, 476, 488, 496 or 515 nm of COHERENT and having a model name INNOVA 400 could be preferably used.

As the IR laser, a Ga / As laser having a wavelength of 847 nm of SPECTRA DIODE LAPS and a maximum power of 100 mW (100 mA) could be an IR laser having a model name SDL-5412-H1 or SDL 800.

As the polarizer, a broad band polarization beam spliter cube of model name 05FC16PB5, which may be used at a wavelength of 620 to 1000 nm of NEWPORT and has an extension ratio of 1000: 1, may be used.

In addition, a multimeter having a model name 34401A of HEWLETT PACKARD could be used as the multimeter.

Therefore, using the polymer material, the recording thin film coated with the same, and the optical device of FIG. 1 according to the present invention, various advantages as follows can be obtained.

First, since a uniform pre-orientation of the liquid crystal polymer is essential when recording information in the known thermal recording method and hologram information storage technology, a special electro-optical cell device is required. I don't need it.

Therefore, there is no energy loss caused by the high voltage applied during full orientation and the possibility of decomposition of organic materials such as azobenzene groups, so there is an advantage that the information of high resolution can be stably stored.

Second, the difference in contrast ratio between the information storage portion induced by the blue polarization and the isotropic portion not exposed to the polarization is very large, so that the ratio of signal / noise (S / N) representing the resolution of the information is very high. There is this.

Third, there is no problem of lowering the contrast ratio (Macromolecules, 24, 42 (1990)) , which has been observed when recording information by heat diffusion in the conventional thermal recording method.

Claims (16)

Dispers Red 1 of the structural formula is a polymer compound for information storage, characterized in that bonded to each other in the side chain of the polymer repeating unit. The method of claim 1, The polymer compound for information storage is a polymer compound for information storage, characterized by the following structural formula: Wherein m is 2, 4, 6, 8 or 10; N is an integer; R is Is; The weight average molecular weight of the polymer compound is about 2,000 to 15,000. The method of claim 1, The information storage compound is a polymer compound for information storage, characterized in that represented by the following structural formula: Wherein n is an integer; remind Represents that two -CH ₂ -bonded to the benzene group are bonded to the ortho, meta, or para position; R is Is; The weight average molecular weight of the polymer compound is about 2,000 to 15,000. The method of claim 1, The polymer compound for information storage is a polymer compound for information storage, characterized by the following structural formula: Wherein n is an integer; R is Is; The weight average molecular weight of the polymer compound is about 2,000 to 15,000. The method of claim 1, The polymer compound for information storage is a polymer compound for information storage, characterized by the following structural formula: Wherein R is Is; X is 3 to 97% in molar ratio; Y is from 97 to 3% in molar ratio; The weight average molecular weight of the polymer compound is about 2,000 to 15,000. An information storage blend copolymer comprising 5 to 30% by weight of the polymer compound according to any one of claims 2 to 4 and 70 to 95% by weight of polymethyl methacrylate or polyvinylcarbazole. (A) dissolving the material of any one of claims 1 to 6 in an organic solvent to prepare a thin film; (b) heating the thin film to the melting temperature of the material used; (c) cooling the heated thin film to a glass transition temperature (T _g ) or less to fix an isotropic state of the thin film polymer. IR laser light source; An optical lens to which light irradiated from the IR light source is incident; A first polarizing plate on which light passing through the optical lens is incident; A recording thin film coated with a material according to any one of claims 1 to 6, positioned on a path of light passing through the first polarizing plate; A second polarizing plate positioned on a path of light passing through the recording thin film and having a polarization axis perpendicular to the polarization axis of the first polarizing plate; And, And an output device for inputting light passing through the second polarizing plate and outputting the information recorded on the recording thin film. The method of claim 8, The IR laser light source is a reversible, optical information reading device, characterized in that the light source of Ga / As having a wavelength of 847nm or He-Ne having a wavelength of 633nm. The method of claim 8, The recording thin film is positioned at an angle of (1 + n) π / 4 ° (where n is 0, 2, 4 or 6) with the polarization axes of the first and second polarizing plates, respectively. Information reading device. (a) applying the substance of any one of claims 1 to 6 on a thin film; (b) heating the coated thin film to an isotropic state by heating at or above the melting temperature of the used polymer, and then quenching below the glass transition temperature (T _g ) of the polymer to form a recording thin film; (c) recording digital information on the recording thin film by using polarized light which is irradiated from an argon laser light source and sequentially passed through a first polarizing plate, a light attenuator, and a wave plate; (d) passing the polarized light which is irradiated from the IR laser light source to the recording thin film on which the digital information is recorded and sequentially passed through the optical lens and the second polarizing plate, and then passing the polarized light perpendicular to the polarizing axis of the second polarizing plate. Reading digital information by passing it through a third polarizing plate and inputting it to an output device; (e) erasing the recorded and read digital information from the recording thin film; And, and (f) rewriting and rereading the information by repeating steps (c) and (d) on the recording thin film on which the digital information has been erased. (a) applying the substance of any one of claims 1 to 6 on a thin film; (b) heating the coated thin film to an isotropic state by heating at or above the melting temperature of the used polymer, and then quenching below the glass transition temperature (T _g ) of the polymer to form a recording thin film; (c) a photomask having a fine pattern recorded thereon is placed on the recording thin film, and then analog information is recorded on the recording thin film by passing polarized light sequentially irradiated from an argon laser light source and passing through the first polarizing plate, the optical attenuator, and the wave plate. Making; (d) passing the polarized light which is irradiated from the IR laser light source to the recording thin film on which the analog information is recorded and sequentially passed through the optical lens and the second polarizing plate, and then passing the polarized light perpendicular to the polarizing axis of the second polarizing plate. Reading analog information by passing it through a third polarizing plate and inputting it to an output device; (e) erasing the recorded and read analog information from a recording thin film; And, and (f) rewriting and rereading the information by repeating steps (c) and (d) on the recording thin film on which the information has been erased. The method of claim 12, The analog information reading step is a step of reading the analog information recorded on the thin film using a low power optical polarizing microscope attached to the second polarizing plate and the third polarizing plate perpendicularly cross each other, reversible, optical information storage method . The method according to claim 11 or 12, The recording thin film is positioned at an angle of (1 + n) π / 4 ° (where n is 0, 2, 4 or 6) with the polarization axes of the second and third polarizing plates, respectively. Information storage method. The method according to claim 11 or 12, In the information erasing step (f), when the wave plate of step (c) has a wavelength of λ / 2, circular polarized light transmitted by the wave plate having a wavelength of λ / 4 is passed through the recording thin film to record information. Reversible, optical information storage method characterized in that the step of erasing from the thin film. The method of claim 11 or 12, The information erasing step of (f) is a step of erasing digital information from the recording thin film by heating the recording thin film above the melting temperature of the polymer compound used, reversible, optical information storage method.