JPH01225617A - Recording medium sheet for optical card - Google Patents

Abstract

PURPOSE:To decrease physical deformation and to improve dimensional stability etc., by curing and molding a polymer soln. obtd. by reacting a specified intermediate product with a vinyl monomer contg. an OH group in a reactive vinyl monomer. CONSTITUTION:An intermediate product (A) is obtd. by reacting an org. dihydroxyl compd. (a) [e.g., 2,2 bis(4-hydroxycyclohexyl)propane] and a diisocyanate (b) (e.g., xylylene diisocyanate) at an equivalent ratio [OH groups of the component (a)/NCO groups of the component (b)] of 0.3-1.0. The compo nent A and a vinyl monomer contg. an OH group (B) of formula I or II (wherein n is 1-20; R1 is a 1-10C alkyl; R2 is a 1-10C alkylene, phenylene or cyclohexylene; R3 is formula III; and m is 1-4) are reacted in a reactive vinyl monomer which acts as a solvent (e.g., styrene) to obtain a polymer soln. contg. 30wt.% final reaction product. This polymer soln. is cured and molded in the presence of a curing agent at room temp. - 200 deg.C for 30sec-10hr.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a recording medium plate for an optical card, which has excellent dimensional stability particularly against temperature and humidity, and which can be coated with various metals and metal oxides by vapor deposition, sputtering, etc. The present invention relates to a recording medium plate for an optical card, which has excellent adhesion of a thin film formed by adhering the same, and has low birefringence, water absorption, and physical deformation due to heat, etc.

(Problems to be solved by conventional techniques and inventions) Conventionally,
Optical cards were made by forming an information storage layer on the surface of a transparent substrate with a low birefringence using methods such as sputtering or vapor deposition, and pasting protective layers on top and bottom of the information storage layer.

However, conventional transparent low birefringence plates, e.g. PMM
A (polymethyl methacrylate resin) has a low glass transition point (Tg) of the polymer itself and is extremely easily deformed by heat. Also, the PMMA mentioned above has a high hydrophilic chemical property, so it does not absorb moisture. When an optical card is made, it tends to warp or otherwise deform due to heat or moisture in the air, and the deformation tends to increase due to changes in temperature.Also, it has high hygroscopicity, so sputtering In processing operations that require high vacuum, such as vapor deposition and vapor deposition, it takes a long time to reach vacuum, resulting in poor workability and other drawbacks.

There have also been attempts to use polycarbonate in similar applications, but this has the drawback of birefringence due to the stress applied when forming the sheet.

On the other hand, in order to eliminate these drawbacks, thermosetting resins have also been developed to which a casting method with less molding stress can be applied. Examples include polydiethylene glycol bisallyl carbonate and JP-A-57-136602.
No. 58-168614 or USP,
Polymers described in Japanese Patent No. 4,443,588 and the like are known.

These polymers have good transparency and higher hardness than thermoplastic resins, but the polymerization reaction rate is very slow, their viscosity is high, making them difficult to handle, and they also have poor abrasion resistance. It has the following disadvantages. Therefore, the above-mentioned thermosetting plastics are mainly used in limited fields such as plastic lenses.

Therefore, an object of the present invention is to have excellent dimensional stability against changes in heat (temperature) and humidity, and to prevent deformation such as warping.
Another object of the present invention is to provide a transparent recording medium plate for an optical card, which has good adhesion to a thin film made of various metals or metal oxides formed by vapor deposition or sputtering, and has low birefringence and low water absorption. be.

[Means to solve problems]

As a result of various studies, the present inventors have found that the above objective can be achieved by reacting predetermined reaction raw materials under specific conditions, curing the resulting polymer solution, and molding it into a predetermined shape. .

The present invention has been made based on the above findings, and consists of (1) using a reactive pinyl momer as a solvent, (2) an organic dihydroxy compound and a diisocyanate at an equivalent ratio of OH group/NCO group of 0.3 to 1.0 ( 7) an intermediate product obtained by reacting within the range, and (3) a hydroxyl group-containing vinyl monomer represented by the following general formula (1) or general formula (2): R.

CHg = C-C-0+Rx9OH(1)CHg
-C-C-0-(-R30-)-rH (21) A recording medium plate for an optical card is provided by curing and molding a polymer solution prepared by reacting -C-C-0-(-R30-)-rH(21).

Next, the optical card recording medium plate of the present invention will be described in detail.

(1) The above-mentioned reactive vinyl monomers include styrene,
Methyl methacrylate, allyl phthalate, diallyl phthalate, divinylbenzene, trimethylolpropane triacrylate, (TMPTA), etc. can be mentioned, and these can also be used as a mixture. Among these, dibylbenzene, TMPTA, methyl methacrylate, and styrene are particularly preferred.

(2) The organic dihydroxy compounds include bisphenol A, halogen-substituted aromatic nuclear hydrogen of bisphenol A, bisphenol S1 hydroquinone, ethylene glycol, propylene glycol, bentanediol,
Hexanediol, 1°4-dihydroxycyclohexane, butanediol, hydroxyphenethyl alcohol, 1. 2-benzenedimetatool, 1.3-benzenedimetatool, 1.4-benzenedimetatool, bis(
Examples of the diisocyanate include hexamethylene diisocyanate Preferred examples include aliphatic diisocyanates such as , tetramethylene diisocyanate, and xylylene diisocyanate.

(3) As the hydroxyl group-containing vinyl monomer represented by the above general formula, 2-hydroxyethyl methacrylate, 2-
Hydroxypropyl methacrylate, 3-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl methacrylate, 4-hydroxybutyl methacrylate, 5-hydroxypentyl methacrylate, 6-hydroxyhexyl methacrylate, 4-hydroxycyclohexyl methacrylate,
4-hydroxyphenyl methacrylate, 3-hydroxyphenyl methacrylate, diethylene glycol monomethacrylate, triethylene glycol monomethacrylate, dipropylene glycol monomethacrylate,
2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 3-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 3-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 3-hydroxybutyl acrylate, 4-hydroxybutyl acrylate, 5- Hydroxypentyl acrylate, 6-hydroxyhexyl acrylate,
Examples include 4-hydroxycyclohexyl acrylate, 4-hydroxyphenylacrylate, 3-hydroxyphenylacrylate, diethylene glycol monoacrylate, triethylene glycol monoacrylate, dipropylene glycol monoacrylate, and the like.

As described above, the recording medium board for an optical card of the present invention has the above-mentioned i.
1 of reactive vinyl monomer as a solvent, the above (2)
It is produced using a polymer solution prepared by reacting the intermediate product of (3) and the hydroxyl group-containing vinyl monomer (3) as a raw material.

The intermediate product of (2) above is obtained by mixing the above-mentioned organic dihydroxy compound and diisocyanate at an equivalent ratio of OH group/NCO group of 0.3 to 1.0, preferably 0.4 to 0.6.・Prepared by reaction. The reaction temperature at that time is 2
The temperature is 0 to 100°C, preferably 50 to 70°C.

If the equivalent ratio of OH group/NCO group is outside the above range, the transparency of the intermediate product will deteriorate, and the properties such as hardness and abrasion resistance of the produced optical card recording medium plate will deteriorate. Although one hour is sufficient, a catalyst such as dibutyltin dilaurate or dimethyltin dichloride may be used to accelerate the reaction.

When the intermediate product in (2) above is reacted with the hydroxyl group-containing vinyl monomer in (3) above, the hydroxyl group-containing vinyl monomer is added to the above intermediate product, and the unreacted NGO group in the intermediate product is The molar ratio of OH group/NCO group is 0.
The reaction is carried out in the range of 3 to 2.0 degrees, preferably in the range of 0.5 to 1.5 degrees.

Further, the reaction between the intermediate product and the hydroxyl group-containing vinyl monomer can be carried out under substantially the same conditions as in the case of preparing the intermediate product, and an organic tin compound can be similarly used as a catalyst.

In addition, when the above-mentioned catalyst is used when preparing the above-mentioned intermediate product and the intermediate product already contains the catalyst,
Furthermore, there are cases where a sufficient reaction rate can be ensured without adding a catalyst.

Further, the amount of the reaction final product relative to the amount of the reactive vinyl monomer (1) used as a solvent is preferably within a range of 30 wt% or more. The final product may no longer dissolve and a uniform solution may not be obtained. However, it is not limited to the above range.

Further, in the recording medium plate for an optical card of the present invention, the polymer solution prepared as described above is cured under predetermined conditions and formed into a plate shape.

The curing reaction of this polymer solution can be carried out using a curing agent, and examples of the curing agent include common polymerization initiators. Specifically, for example, organic peroxide (
Perbutyl Pv1 Perbutyl D, Perbutyl Z1 Perhexa V, manufactured by Nihon Yushi Corporation.

Preferred are radical polymerization initiators such as Perloyl IPP, Verhexa H, Perbutyl ■, Perhexa C, Perbutyl F1 Berkmil P, etc.), azo compounds (azoisobutyllonitrile), and iniferter polymerization initiators (tetraphenylethane). can be mentioned.

The curing reaction can also be initiated by physical energy such as electron beams, radiation, light, heat, etc. that can initiate polymerization.

As a method for forming the recording medium plate for an optical card, a known curing/forming method such as a casting method or a casting polymerization method using a glass plate can be employed.

The amount of the curing agent used is 0.01% of the polymer solution.
wt% to 5wt%, preferably 0.05 to 2wt%, and the curing temperature is room temperature to 200°C, preferably 60°C.
~150°C. Depending on the initiator, it is also possible to carry out superheat curing in stages within a certain temperature range. The curing time varies depending on the type of initiator and the amount added, but it is usually 30
From seconds to 10 hours at the most. It goes without saying that additives such as a mold release agent and various stabilizers can be added before curing.

Next, preferred embodiments of the present invention will be described.

(Example 1) 2264 g of styrene was placed in a 51 glass flask,
While stirring, 6 moles (1) of xylylene diisocyanate (65 g) was dissolved therein, and 0.17 g of dibutyltin dilaurate was added as a catalyst and dissolved.Then, the above solution was heated to 50°C and dissolved in a flask. 2.
2-bis(4-hydroxycyclohexyl)propane 3
mol (707 g) was gradually added, and after the addition was completed, the reaction was continued for 2 hours at 60°C.

Thereafter, the mixture was cooled to 50° C., and 6.25 mol (902 g) of 2-hydroxypropyl methacrylate was added dropwise to react. At this time, since it was an exothermic reaction, it was cooled to prevent the temperature from rising above 60°C. After the completion of the dropwise addition, the reaction was continued at 60°C for 4 hours. Then, while cooling to room temperature, methoxyhydroquinone was added to the reaction solution. It was dissolved and the concentration was set to 1)000PP. This reaction solution was filtered under pressure through a filter with a pore size of 5 μm to remove dust and the like therein to obtain a polymer solution. The viscosity of the polymer solution thus obtained was 250 CPS at 25°C.

A portion of the polymer solution prepared as described above was taken and cured and molded into a plate shape with a thickness of 0.6 nm by a casting method using a glass plate under the following curing conditions. At that time, peroxide (trade name: Perbutyl I) is used as a curing agent.
・Q, 3 wt (manufactured by NOF) to the resin solution
% and cured at 85°C for 1 hour at 120°C.
1 hour at 130℃ and another 1 hour at 130℃ for a total of 3 hours.
A transparent flat plate molded product (recording medium plate for optical card) was created by performing the process in stages.

This flat plate molded product was subjected to various physical property tests to evaluate its performance as an optical card material, and the results are shown in Table 1 below. Incidentally, the physical property test was conducted in the following manner.

+1) Appearance: The flat plate molded product was observed with the naked eye.

(2) Light transmittance; light transmittance (%) at 830 nm (
3) Hardness: Pencil hardness, JIS K5401 pencil scratch method for paint films (4) Impact strength: Measured according to ASTM D256 (
-・cs/cm ) (5) i refraction: by 2P method (6) adhesion of metal thin film; target is Cr on the surface of flat molded product, RF power is 100W.

After sputtering Cr under the condition of argon gas pressure of 0.5 Pa, a substrate peeling test was conducted in accordance with JI3-0202-8-12.

(7) Water absorption rate; flat plate molded product (100 cranes x 100
, 1) n) was immersed in water at 25°C for 24 hours and then taken out, and the weight increase rate (%) of the molded product compared to before immersion.

(8) Chemical resistance: Comprehensive evaluation by observing changes in the surface state of the flat molded product after immersing it in isopropyl alcohol or acetone for 10 hours, measuring changes in weight, etc.

[Examples 2 to 10] For Examples 2 to IO using the following organic dihydroxy compound in place of 2,2-bis(4-hydroxycyclohexyl)propane in Example 1, a flat plate molded product was prepared in the same manner as in Example 1. was prepared and evaluated for performance, and the results are also shown in Table 1 below.

That is, in Example 2, 1. 6-hexanediol, hydroquinone in Example 3, bisphenol A in Example 4, ethylene glycol in Example 5, and 1 in Example 6.
．． 4 dihydroxycyclohexane, bisphenol S in Example 7, 1°4-benzenedimetatool in Example 8, 1,4-butanediol in Example 9, Example 10
This is polybutadiene having hydroxyl groups at both ends. The amount of each compound used was equimolar as in Example 1. still,
In Example 4.5.8, the xylylene diisocyanate of Example 1 was further replaced with equimolar hexamethylene diisocyanate.

[Comparative example]

Methyl methacrylate (MMA) was cured and molded using the glass casting method in the same manner as in Example 1, and a 1 m flat plate molded product was created for comparison. The performance of this flat plate molded product was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

[Examples 1) to 20] For Examples 1) to 20, in which the following hydroxyl group-containing and nil monomers were used in place of 2-hydroxypropyl methacrylate in Example 1, flat molded products were created in the same manner as in Example 1. The performance was evaluated using the following methods, and the results are shown in Table 2 below.

That is, 3-hydroxypropyl acrylate in Example 1), 4-hydroxybutyl methacrylate in Example 12, 6-hydroxymethacrylate in Example 13,
Diethylene glycol monomethacrylate in Example 14, dipropylene glycol monomethacrylate in Example 15, 4-hydroxycyclohexyl acrylate in Example 16, 4-hydroxyphenyl methacrylate in Example 17, 4-hydroxybutyl acrylate in Example 18, Example 19 uses 4-hydroxycyclohexyl acrylate, and Example 20 uses diethylene glycol monoacrylate. The amount used is equimolar as in Example 1. In Examples 14 to 20, an equimolar amount of bisphenol A was used in place of 2.2bis(4-hydroxycyclohexyl)propane. The obtained polymer solution was cured and molded by the casting method using a glass plate in the same manner as in Example 1 to create a flat plate molded product having a size of 0.6 cranes. Physical property tests were conducted on this flat plate molded product in the same manner as in Example 1, and the performance evaluation results for each Example are shown in Table 2.

〔Effect of the invention〕

The recording medium plate for an optical card of the present invention has excellent dimensional stability against changes in heat (temperature) and humidity, is resistant to deformation such as warping, and is made of various metals or metals formed by vapor deposition or sputtering. It has good adhesion to thin films such as metal oxides, and has low birefringence and low water absorption.

Claims (3)

[Claims] (1) Using a reactive vinyl monomer as a solvent, (2) an intermediate product obtained by reacting an organic dihydroxy compound and a diisocyanate with an OH group/NCO group equivalent ratio in the range of 0.3 to 1.0, and (3) Hydroxyl group-containing vinyl monomer represented by the following general formula (1) or general formula (2): ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ (1) [n = integer from 1 to 20. R_1 = hydrogen or an alkyl group of C_1 to C_1_■. R_2=C_1 to C_1_■ alkylene group, phenylene group or cyclohexylene group. ] ▲There are mathematical formulas, chemical formulas, tables, etc.▼(2) [R_1, n are the same as in general formula (1). R_3=C_2_mH_4_m, m=an integer from 1 to 4. ] A recording medium board for an optical card obtained by curing and molding a polymer solution prepared by reacting the following.