JPS63317521A - Optical disk substrate - Google Patents

Abstract

PURPOSE:To obtain an optical disk substrate having excellent heat resistance, mechanical strength and optical properties, by molding a polymer composition consisting essentially of a ring opening polymer of a norbornene derivative having polar groups and irradiating the resultant molded disk with active energy rays. CONSTITUTION:The aimed disk substrate obtained by molding a polymer composition, prepared by subjecting (A) a norbornene derivative containing polar groups consisting of nitrile group, ester group, chlorine atom, acid anhydride group and/or imide group or <=20C hydrocarbon residue containing the above- mentioned polar groups or (B) a mixture consisting of the component (A) and <=50mol.% cycloolefin based compound or a norbornene derivative having aromatic hydrocarbon group, ether group, amide group and/or bromine atom to ring opening polymerization and consisting essentially of a ring opening polymer and irradiating the resultant molded disk with active energy rays.

Description

Detailed Description of the Invention Toru -, To 1 The present invention uses a ring-opening polymer of polar group-substituted norbornene as a substrate material for digital audio discs, video discs, memory discs, etc. (hereinafter referred to as optical discs). The present invention relates to an optical disc having excellent optical properties obtained by wire crosslinking.

To date, many resins have been developed as disc materials.
It is put into practical use. For example, inorganic glass, polymethyl methacrylate (hereinafter abbreviated as PMMAJ),
Examples include polystyrene and polycarbonate resin, but when comprehensively evaluating the physical properties as a disk material, they all have advantages and disadvantages, and are not necessarily satisfactory.

In the case of inorganic glass, it has the advantage of having little adverse effect on the recording film due to its low hygroscopicity, but has disadvantages such as being heavy and easily broken, and furthermore, precision processing of the glass is expensive. On the other hand, resin materials are superior to inorganic glass in terms of specific gravity cracking moldability as described above, but their overall performance as a disk material, including dimensional stability, is still insufficient.

That is, in the case of PMMA, there are problems in terms of heat resistance, water absorption, impact resistance, etc. In addition, although polycarbonate resin (hereinafter abbreviated as rPCJ) has the above characteristics to some extent, the resin has poor fluidity and a large photoelastic constant, which causes birefringence in the molded product. The problem is that the data becomes large and many errors occur in the information recorded on the disc.

In general, when thermoplastic resins such as PMMA and PC are used as materials for optical disc substrates, the temperature of the substrate surface becomes high when information is written with high-power laser light. There is a problem in that the guide grooves called the closed groups disappear.

In order to solve these problems, proposals have been made to use cross-linked resins such as epoxy resins to obtain optical disc substrates by casting, but the curing time of the resin is long, resulting in a long molding cycle. , which has fatal flaws that reduce productivity and increase costs.

Furthermore, as seen in Japanese Unexamined Patent Publication No. 81-9436, it has been proposed to obtain an optical disk substrate by irradiating a composition in which methyl methacrylate and P-methylstyrene are copolymerized. There are drawbacks to the properties of the resin itself, and good optical disc substrates have not been obtained.

As described above, each material has its advantages and disadvantages, and at present it is not possible to obtain a good optical disk substrate.

As a result of intensive studies in order to obtain an optical disc substrate free of the above-mentioned drawbacks, the present inventors have developed a composition mainly consisting of a ring-opening polymer of norbornene substituted with a polar group. The inventors have discovered that by using a wire-crosslinked material, it is possible to provide an optical disc with excellent heat resistance, mechanical strength, and optical properties, and have arrived at the present invention.

・・・The present invention does not have the drawbacks of the prior art described above, and uses (i) a group consisting of a nitrile group, an ester group, a chlorine atom, an acid anhydride group, and an imide group as an optical disc material. a norbornene derivative having at least one polar group selected from or a hydrocarbon residue having at most 20 carbon atoms containing the polar group, or (ii) the norbornene derivative and at most 50 mol% of a cycloolefin. The main component is a ring-opening polymer obtained by ring-opening polymerization of a mixture consisting of an aromatic hydrocarbon group, an aromatic hydrocarbon group, an ether group, an amide group, and a norbornene derivative having at least one group selected from the group consisting of a bromine atom. This is an optical disk substrate characterized by irradiating active energy rays onto a disk formed by molding a resin composition.

The norbornene derivatives having a polar group or a substituent containing a polar group used as a monomer in the present invention are:
Nitrile norbornene derivatives, ester norbornene derivatives, chlorine norbornene derivatives, acid anhydride norbornene derivatives, imide norbornene derivatives, aromatic norbornene derivatives, ether norbornene derivatives, amide norbornene derivatives, and brominated norbornene derivatives. be.

Among the nitrile-based norbornene derivatives used as monomers to produce the ring-opening polymer in the present invention, the general formulas of typical ones are shown by the following formulas and ((I)).

[Tatashi, Wl, XI, YI and Zl may be the same or different, hydrogen atom, cyano group and tolyl group), alkyl group having at most 20 carbon atoms substituted with 7 cya groups, cycloalkyl group, alkenyl groups and allyl
) or hydrocarbon groups selected from the group consisting of alkyl groups, alkenyl groups, cycloalkyl groups, aryl groups and aralkyl groups having at most 20 carbon atoms. Although the base is Wl
, xl, Yl and zl, at least one is a hydrocarbon group substituted with a cyan group or a cyano group] Nitrile type used as a monomer to produce a ring-opening polymer in the present invention Among the norbornene derivatives, a typical example is 5-cyano-bicyclo(2,2,1)
-hebutene-2 can be mentioned. Furthermore, other representative examples of nitrile norbornene derivatives used as monomers in the present invention include those described in JP-A-49-87999.

To produce a ring-opened polymer in the present invention? Among the ester-based norbornene derivatives which are used as JH+, representative examples are those represented by the general formulas of the above formula (I) and the following formula (formula (II)).

[Tatashi, Wl, XI, Yl and Zl and W2.
X2, Y2 and Z2 are hydrogen atoms, ester groups [general formula 100OR+ or 1000RI (however, R1 is 1
2 prime numbers represented by at most 20 hydrocarbon groups],
Hydrocarbon group substituted with ester group [general formula is -R2C
0OR+ or R20CORI (wherein R1 is the above hydrocarbon group, R2 is a divalent hydrogen group having at most 20 carbon atoms), W', X',
At least one of Y' and t*, W2, x2, Y2 and Z2 (7) is an ester group or a hydrocarbon group substituted with an ester group] Also, in the present invention, a ring-opening polymer is produced Among typical ester-based norbornene derivatives used as monomers for
) and (IV)].

(m) [However, A is -Coo-R3-00C- or -CO
OR4-(?:dari, R'', J: and R4 are alkylene groups having at most 20 carbon atoms), and W3, Z3 and W4, x4, Y4, J: and z4 may be the same or different. , a hydrogen atom or the above-mentioned ester group, a hydrocarbon group or hydrocarbon group containing an ester group, W4,
At least one of X4, Y4 and Z4 is an ester group or a hydrocarbon group substituted with an ester group]
In carrying out the present invention, among the ester-based norbornene derivatives represented by the above general formula, the ester-based norbornene derivative represented by the formula (I) is particularly desirable.
A typical example is 5-methoxycarbonyl-
Bicyclo(2,2,1)-hebutene-2,5-ethoxycarbonyl-bicyclo(2,2,1,)-hebutene-
2,5-propoxycarbonyl-bicyclo-2,5-allyloxycarbonyl-bicyclo[2.

2,1]-hebutene-2,5-methyl-5-methoxycarbonyl-bicyclo(2,2.1)-hebutene-
2 etc. can be mentioned.

Among the ether type norbornene derivatives used as monomers to produce the ring-opening polymer in the present invention, the general formulas of typical ones are shown in the above formulas (I), (II) and (m). It is something that can be done.

[However, Wl, XI, Yl and Zl and W2,
x2, Y2 and Zl, and W3 and Z3 may be the same or different, and each represents a hydrogen atom, an ether group, or a hydrocarbon group containing an ether group [the general formula is -R20R+- (wherein, R1 is the same as R1 above, R2 is a carbon At most 20
) or the above-mentioned hydrocarbon group, W I , X I , Y l Oyo I
JZ' Oak U Ni W2, x2. Among Y2 and Zl,
At least one is an ether group or a hydrocarbon group substituted with an ether group, and A has the general formula -R30R4-
or -R50- (However, R3, R4 and R5 may be the same or different, and are hydrocarbon groups having at most 20 carbon atoms)] In the present invention, a ring-opening polymer is produced. Among the ether-based norbornene derivatives used as monomers for
,l)-hebutene-2,5-ethoxy-bicyclo(2
, 2°1]-hebutene-2, etc.

In the present invention, the general formulas of one representative amide norbornene derivative used as a trifluoride to produce the open Ii:1 polymer are the formulas (I), (TI) and (III) above. It is what is shown.

However, in formulas (I) and (III), Wl,
XI, Ylt-(J: BiZ' Oak UL: W 2, x
2, Y2 and Zl and W3 and Z3 may be the same or different, and each represents a hydrogen atom, an amide group (-CON-R1)
, a hydrocarbon substituted with an amide group (-R3CON-
R1) or the above hydrocarbon group, WI, xl, Yl
and Zl or W2, X2, Y2 and Zl,
At least one is the amide group or a hydrocarbon group substituted with an amide group. l(+ and R2 may be the same or different, and are hydrocarbons having at most 20 carbon atoms,
R3 is a divalent hydrocarbon group having at most 20 carbon atoms. A has a general formula of - (wherein R4, R3 and R
6 may be the same or different, and is a fullkylene group having at most 20 carbon atoms.

Furthermore, in the present invention, in the formula (I), Wl
, Xl, Y I t-J, Z' (7), an alkylene group having at most 20 carbon atoms) can also be used as a monomer.

Among the amide norbornene derivatives used as monomers to produce the open g5@combinant in the present invention, typical examples include N,N-dimethyl-bicyclo(2
,2,l)-hebutene-2-carbonamide-5,N
, N-diethyl-bicyclo(2,2,I)-hebutene-2-carbonamide-5, and the like. 1 more
Other representative examples of amide norbornene derivatives used as monomers in the present invention are disclosed in JP-A-50-153100.
It is stated in the specification of the No.

Among the chlorinated norbornene derivatives used as a monomer to produce the ring-opening polymer in the present invention, the general formulas of typical ones are those shown by the above formulas (I) and (II). .

However, in formula (I) and formula (rr), Wl,
xl, Yl and Zl and W2, x2, Y2 and Zl may be the same, hydrogen atom, chlorine atom, bromine atom,
A hydrocarbon group having at most 20 j vacancies or a hydrocarbon group having at most 20 carbon atoms substituted with at least one chlorine atom, Wl, XI, Yl and Z't or W2, x2 , Y2 and Zl, at least one is a hydrocarbon group substituted with a single atom.

One representative example of the chlorinated norbornene derivatives used as a monomer to produce the ring-opening polymer in the present invention is 5-chloro-bicyclo(2,2,1).
-hebutene-2,5,6-bischloromethyl-bicyclo(2,2,1)-hebutene-2 and the like.

Further, other representative examples of chlorinated norbornene derivatives used as monomers in the present invention are disclosed in Japanese Patent Application Laid-Open No. 50-153.
No. 100 and No. 51-55400.

Among the brominated norbornene derivatives used as monomers to produce the ring-opening polymer in the present invention, the general formulas of typical ones are those shown by the above formulas (I) and (II).

However, in formulas (I) and (II), Wl,
xl, Yl and Z'A'' W2, x2, Yl
and Z2 may be the same, and may be a hydrogen atom, a chlorine atom, a bromine atom, a hydrocarbon group having at most 20 carbon atoms substituted with at least one bromine atom, or a hydrocarbon group having at most 2 carbon atoms.
0 hydrocarbon groups, Wl, Xl, Yl and Z
At least one of 't, W2, X2, Yl and Z2 is a hydrocarbon group substituted with a bromine atom.

Among the brominated norbornene derivatives used as monomers to produce the ring-opening polymer in the present invention, a representative example is 5-bromo-bicyclo(2,2,l
)-Hebutene-2,5-bromo-5-methyl-bicyclo(2,2,1)-hebutene-2,5-bromo-6-methyl-bicyclo(2,2,1)-hebutene-2 etc. can be mentioned.

Furthermore, other representative examples of the brominated norbornene derivatives used as monomers in the present invention are disclosed in Japanese Patent Application Laid-Open No. 50-153.
No. 100 and No. 51-55400.

Further, among the acid anhydride norbornene derivatives used as monomers in the present invention, the general formulas of typical ones are shown by the following formulas [Formula (V) and Formula (Vl)].

(Margin below) (V) [However, W3 and Z3 and W6 and x6 may be the same or different, and are hydrogen atoms or hydrocarbon groups having at most 20 carbon atoms, and B is a hydrocarbon group having 4 to 20 carbon atoms. ] (V) and (VT) formulas In, when q is 0, the carbon of the norbornene ring and the acid anhydride-containing carbon form a monocyclic ring.

One representative example of the acid anhydride norbornene derivatives used as monomers to produce the ring-opening polymer in the present invention is 3,6-methylene-1,2,
3,6-titrahydrosis-phthalic anhydride, 5-(
5-carboxy-bicyclo[2゜2.1]-hebuta-2
-enyl) acetic anhydride. Furthermore, other representative examples of acid anhydride norbornene derivatives used as monomers in the present invention are described in JP-A-50-58200.

Among the imide-based norbornene derivatives used as monomers to produce the ring-opening polymer in the present invention, among the general formulas of typical ones, the formulas (V) and (Vl) are as examples. It is what is shown.

However, in the formula, D is one whose general formula is >N-R1 (However, l(+ means that the number of carbon atoms is at most 2
(containing 0 hydrocarbon group or ester group), where B, letter, m and q are the same as in the case of the dianhydride-based norbornene derivative.

The general formula of other imide-based norbornene derivatives is the following formula [(■
) formula].

(■) [However, Wl, Yl and R7 may be the same or different, and are a hydrogen atom or a hydrocarbon group having at most 20 carbon atoms, and R2 is a fullylene group having 2 to 6 carbon atoms,
alkenylene group or arylene group, and n is 0.1 or 2] Among the imide-based norbornene derivatives used as intermediates to produce the ring-opening polymer in the present invention, typical ones include: N-methyl-3,6
-methylene-1,2,3,6-titrahydrosis-phthalimide, N-ethyl-3,6-methylene-1,2,
3,ff-tetrahydro-cis-phthalimide. Also, 1. General formulas of imido-based norbornene derivatives used as monomers in the present invention and methods for their production, N-substituted-3,6-substituted imide-based norbornene derivatives.
-methylene-1゜2,3.8-tetrahydro-cis-phthalimide compounds and N-(ω-(5-norborn-2-enyl)) substituted maleimide compounds, representative examples of compounds, and other imido-based norbornene derivatives. A representative general formula is described in Japanese Patent Application Laid-open No. 75300/1983.

Furthermore, the general formula of the aromatic norbornene derivative used as a monomer to produce the ring-opening polymer in the present invention is the above-mentioned formula (1) and (!I) formula (7) Wl, Xl,
Yl and Zl and w2,
Aromatic hydrocarbons having a total of 3 aromatic rings substituted with 0 alkyl, cycloalkyl, or alkenyl groups, or other hydrocarbon groups (the total number of carbon atoms is at most 30) Based on Wl.

Xl, Ylt-JJ: BiZ't1iW2, X2, Yl
At least one of R2 and R2 is an aromatic hydrocarbon group. Structural formulas of these aromatic hydrocarbon groups and representative examples of hydrocarbon groups substituted for the aromatic hydrocarbon groups are given in JP-A-50-153100 and JP-A-50-153100.
-160400, each clear fB PI.

A representative example of the aromatic norbornene derivative used as a monomer to produce the ring-opening polymer in the present invention is 5-phenyl-bicyclo(2,2,1)-hebutene-2. Representative examples of other aromatic norbornene derivatives used as monomers in the present invention are described in the specifications of JP-A-50-153100 and JP-A-50-180400.

The aromatic norbornadiene derivative used as a monomer to produce the ring-opening polymer in the present invention has bicyclo(2,2,l)-hebutene-2 (norbornene) at the 5th and 6th positions. It is a compound that shares a carbon atom with two adjacent carbon atoms of an aromatic cyclic compound, and its general formula is represented by the following formula ((Vff[) , (IX) ).

[However, El, R2, R3, R4, R5 and R6 may be the same or different, and each has a hydrogen atom and a carbon number of at most 10
Hydrocarbon groups or cyano groups selected from the group consisting of alkyl groups, alkenyl groups, cycloalkyl groups, allyl (ar71) groups and aralkyl groups, halogen atoms, and ester and ether groups having at most 10 carbon atoms. A polar group selected from the group consisting of or the above-mentioned hydrocarbon group substituted with the polar group] As a representative example of the aromatic norbornadiene:A conductor used as a monomer in the present invention, l.

4-dihydro-1,4-methanonaphthalene is mentioned. Other representative examples of aromatic norbornadiene derivatives used as the m H form in the present invention include JP-A No. 50-81
It is described in Publication No. 500.

Further, a typical example of the ester-based norbornadiene derivative used as a monomer to produce the ring-opened polymer in the present invention is represented by the following formula [Formula (X)].

(X) [However, X8 and Y8 may be the same or different, and may be a hydrogen atom, a hydrocarbon having at most 20 carbon atoms, or a compound having the general formula -(CH2) m COOR' and -(CH2
) n OCOR" (where R' and R" are hydrocarbons having at most 20 carbon atoms) an ester group represented by 1 (, m and n are integers of 0 or 1-10), (or an ester group) The groups containing x8 and Y8
At least one of them is Estherno. Representative examples of ester-based norbornadiene derivatives used as monomers in the present invention (or containing an ester group) include 2-methoxycarbonyl-bicyclo(2
,2,l)-hebuta-2,5-diene and 2-ethoxycarbonyl-bicyclo(2,2,l)-hebuta-2.

In the present invention, the cycloolefin compounds used as comonomers to copolymerize with the monomers described above are broadly classified into monocyclic monoolefin compounds, non-conjugated cyclic polyene compounds, and polycyclic olefin compounds. Ru.

Used as a comonomer? ! The general formula of the i-cyclic monoolefin compound is represented by the following formula (Formula (XI)).

(However, n is an integer of 3 to 20) Representative examples of monocyclic monoolefin compounds used as comonomers include cyclopentene, cycloheptene, cyclooctene, cyclodecene, and cyclododecene, and monocyclic monoolefin compounds of these compounds. Examples include monocyclic monoolefin compounds in which a methylene carbon is substituted with one or more hydrocarbon groups having at most 10 carbon atoms selected from the group consisting of alkyl groups, alkenyl groups, and aryl groups.

Further, the general formula of the non-conjugated cyclic polyene compound used as a comonomer in the present invention is represented by the following formula ((X[[) and (Xlff) formula]).

(CH2)n (X[I) (■) (where l is O or an integer from 1 to 20, m and n are 2 to
(an integer of 20) Representative examples of non-conjugated cyclic polyene compounds used as comonomers include 5-cyclooctadiene and 1,5,9-cyclooctadiene. Furthermore, a non-conjugated cyclic polyene system substituted with one or more [1)] hydrogen and/or halogen atoms in the non-conjugated cyclic polyene system compound represented by the formulas (X[I) and (XI[[)] Compounds (e.g. 1-chloro-1,
5-cyclooctadiene and l-methyl-1,5-cyclooctane) can also be used.

Furthermore, the monocyclic olefin compound used as a comonomer in the present invention has 2 to 10 rings, and carbon-
It is a compound having 1 to 5 carbon double bonds, and its representative example is bicyclo[2゜2.1]-hebutene-2.
(norbornene), 5-methyl-picycloil: 2.2
．． 1)-hebutene-2.

- Among the monomers listed below, nitrile norbornene derivatives, ester norbornene derivatives, ether norbornene derivatives, amide norbornene derivatives, chlorinated norbornene derivatives, acid anhydride norbornene derivatives, brominated norbornene derivatives, aromatic norbornene derivatives,
Aromatic nitrogen-containing heterotonic norbornene derivatives and some cycloolefin compounds (for example, 5-methyl-bicyclo(2,2,1)-hebutene-2) are all endo( There are isomers having an endo type and an exo type, but in producing the ring-opened polymer in the present invention, these isomers can be separated by separation methods such as precision distillation method and recrystallization method. They may be separated and used, but they may also be used as they are without separation (that is, they may be used as a mixture of isomers).

In the following monomers-E, the <1i-mer represented by formula (I) is generally a compound having one corresponding double bond (for example, acrylonitrile, methyl methacrylate, vinyl acetate, vinyl chloride, vinylidene chloride,
It is produced by the Diels-Alder reaction of styrene) and cyclopentadiene or dicyclopentadiene, but monomers of formula (II) are also obtained [in this reaction, the monomer of formula (I) and ( The production ratio of the monomer represented by the formula (H) varies depending on the reaction conditions], and the monomer represented by the formula (II) is mixed with the monomer represented by the formula (I) and cyclopentadiene or dicyclopentadiene. The monomer represented by the formula (I), which is a raw material, may remain unreacted even in this case. In any of the above cases, if the monomer represented by the formula (1) and the monomer represented by the formula (TI) are obtained as a mixture, these monomers are processed by precision distillation method and recrystallization method. It can be separated by the following separation methods. In carrying out the present invention, these intermediates may be used after being separated, or may be used without being separated.

In carrying out the present invention, only one type of monomer (including cycloolefin compounds used as comonomers) may be used, or two or more types may be used in combination.

Further, the copolymerization ratio of the cycloolefin compound as a copolymerization component is at most 50 mol%, preferably 45 mol% or less, and particularly preferably 40 mol% or less.

The present invention can be carried out by ring-opening polymerization of the above-mentioned norbornene derivative, norbornene derivative, norbornadiene derivative, or said compound, and at most 50 mol% of a cycloolefin compound and/or norbornene using an appropriate catalyst system. Able to achieve target.

Examples of catalysts used to obtain the catalyst system used in the present invention include non-pulverized products of organometallic compounds and transition metal compounds and metal hydroxides disclosed in JP-A No. 52-42800. The catalyst system obtained from

Although the catalyst system used for ring-opening polymerization in the present invention varies depending on its type, the ratio of the transition metal compound to 1000 moles of monomer is generally 0.001-
100 mol, preferably 0.005 to 50 mol,
In particular, 0.1 to 10 mol is suitable. monomer 1000
If the proportion of the transition metal compound used is less than 0.001 mole per mole, sufficient polymerization activity cannot be obtained; on the other hand, 1
If 00 moles or more of the transition metal compound is used, it is not preferable because it will require a lot of effort to remove the catalyst, and the resulting ring-opened polymer will be colored.

The present invention uses a co-pulverized product obtained by co-pulverizing the monomer described above with an organometallic compound, a transition metal compound, and a metal hydroxide, or a catalyst system obtained from these and a third component. The ring-opening polymerization may be carried out in the absence of an inert organic solvent (ie, bulk polymerization), but the ring-opening polymerization may also be carried out in an inert organic solvent. The organic solvent preferably has a melting point of 30"C or less, and 2
A temperature of 0°C or lower is preferred, and a temperature of 10°C or lower is particularly preferred. Its dropping point is preferably 500°C or less, preferably 400°C or less,
Particularly suitable is one having a temperature of 300'C or less.

Inert organic solvents include aliphatic hydrocarbons such as pentane, hexane, heptane, octane and decane, aliphatic hydrocarbons such as cyclopentane and cyclohexane, aromatic hydrocarbons such as benzene, toluene and xylene, methylene chloride, ethyl chloride, I,
1-dichloroethane, 1,2-dichloroethane,! ,
2-dichloroethylene, l-chloropropane, 2-chloropropane, l-chlorobutane, 2-chlorobutane, ■
-chloro-2-methylpropane, l-chloropenkune,
Examples include halogenated hydrocarbons such as chlorobenzene, 0-dichlorobenzene, m-dichlorobenzene and p-dichlorobenzene, ethers such as dichlorobenzene, diethyl ether and tetrahydrofuran. When carrying out unreleased 1s1 in an inert organic solvent, these inert organic solvents may be used alone or as a mixture of two or more. In carrying out the ring-opening polymerization in the organic solvent, the proportion of the organic solvent used per 1 part by volume of the monomer is generally at most 20 parts by volume, preferably 10 parts by volume or less. If the ratio of the organic solvent used is less than 20 parts by volume per 1 part by volume of the monomer, it will be troublesome to recover the ring-opened polymer obtained after the polymerization is completed. Furthermore, it is difficult to recover the used organic solvent.

The polymerization temperature is generally -100 to +200°C,
In particular, -50 to +150°C is preferable, especially 0
~120°C is preferred. The polymerization temperature is one! Since there is no sufficient polymerization activity below 00°C, the polymerization rate is very slow, and therefore a long time is required for ring-opening polymerization. Furthermore, the mixture of the monomer or monomer and the inert organic solvent may solidify.

On the other hand, when the polymerization temperature is 200° C. or higher, it is often difficult to sufficiently control the polymerization. The ring-opening polymerization is preferably carried out in an atmosphere of an inert gas such as argon or nitrogen. If oxygen and moisture (moisture) are present in the polymerization system, part or all of the catalyst system used in the present invention will deteriorate. Therefore, reproducible results cannot be expected.

After completion of the ring-opening polymerization, the resulting polymer can be recovered by several methods. As an example of the recovery method, a method for removing the catalyst and recovering the polymer that is commonly used in solution polymerization of isoprene, butadiene, etc. may be applied. For example, a solvent containing a lower alcohol (e.g., methyl alcohol, ethyl alcohol) or a ring-opening polymer obtained by ring-opening polymerization of the alcohol containing a small amount of hydrochloric acid, unreacted monomers, catalyst residue, etc. Method of precipitating the resulting ring-opened polymer at the same time as the catalyst residue is removed by pouring the resulting ring-opened polymer, an organic solvent containing unreacted monomers, catalyst residue, etc., and water. After homogenization with an inert organic solvent (e.g. methylene chloride),
Chelating agents (e.g. ethylenediaminetetraacetic acid,
Examples include a method of treating with water containing nitrilotriacetic acid), then removing the catalyst, and then removing the organic solvent.

The present invention is to obtain a good optical disk substrate by irradiating active energy rays onto a disk substrate formed by molding a composition mainly composed of the ring-opened polymer obtained as described above to cause crosslinking. .

The active energy rays used in the present invention include ultraviolet rays, gamma rays, beta rays, alpha rays, binary rays, and electron rays.

When ultraviolet rays are used as active energy rays, they may be irradiated as they are. Initiators and/or sensitizers may be used to improve reaction efficiency. As the initiator, a cleavage type or a hydrogen abstraction type can be used.

For example, acetophenone, benzophenone, Michler's ketone, benzyl, benzoin, benzoin alkyl ether, benzyl dimethyl ketal, tetramethylthiuram monosulfide, thioxanthone, 2-chlorothioxanthone, p-isopropyl-α-hydroxyisobutylphenone, α-hydroxyisobutylphenone , 2.2-dimethoxy-2-phenylacetophenone,
1-Hydroxycyclohexylphenyl ketone, hendiine isobutyl ether, benzoin isopropyl ether, p-tert-butyltrichloroacetophenone, p-tert-butyldichloroacetophenone, n
-butyl or imbutylbenzoin ether, 1-phenyl-1,2-propanedione-2-(0-ethoxycarbonyl)oxime, 2-methylthioxanthone, dibenzosuberone, α,α-dichloro-4-phenoxyacetophenone, 2- Examples include nityl anthraquinone benzoin alkyl ether.

A sensitizer can also be used, and if used in combination with the above-mentioned initiator, the effect will be even greater.

For example, amines include aliphatic amines, amines containing aromatic groups, nitrogen Zm2-ring compounds such as piperidine, ureas include allyl and O-)lylthiourea, and sulfur compounds include sodium diethyldithiophosphate and aromatic Soluble salts of sulfinic acids, nitrile compounds include N, N-disubstituted-P-aminobenzonitrile compounds, phosphorus compounds include tri-n-butylphosphine and sodium diethylthiophosphate, and other nitrogen compounds include Michler's ketone and N -Nitrone hydroxylamine derivatives, oxazoline compounds, etc., 11! Carbon tetrachloride, hexachloroethane, etc. can be used as elementary compounds.

The amounts of these initiators and sensitizers used are as follows:
The total amount is preferably 5 parts by weight or less relative to 0 parts by weight. If it exceeds 5 parts by weight, problems such as coloring and brittleness of the molded product will occur.

In addition, the amount of ultraviolet irradiation is 0. IJ/cm'
to 10,000 J/c rn',
Furthermore, 1 J / crn' ~ 7000 J /
cm' is more preferred.

Irradiation amount is 0. If it is less than IJ/cm', a sufficient cross-linking reaction will not occur, and it will not be effective in preventing group disappearance during laser writing, and if it is irradiated in excess of 100OOJ/cm', it will be colored and the optical disc substrate You can't get anything as good as that.

In the present invention, in addition to ultraviolet rays, radiation such as comma rays, beta rays, alpha rays, X-rays, and electron beams can be used as active energy rays.

The dose of these radiations is preferably 10-100 Mrad. If the irradiation dose is less than 10 Mrad, sufficient crosslinking will not occur and the improvement in physical properties will be small. 100Mr
If the amount is more than ad, the resin will deteriorate.

Irradiation with active energy rays is performed after the resin composition is molded into the shape of an optical disk. The irradiation method may be one-time irradiation or one or more divided irradiation methods.

The resin composition used in the present invention has excellent transparency, fluidity, heat resistance, and water resistance. Furthermore, the resin composition used in the present invention has excellent transparency, fluidity, heat resistance, and water resistance, and furthermore, the water irradiated with active energy rays makes it an excellent optical disc substrate material and an optical disc. The water will provide the substrate. Furthermore, stabilizers against light (ultraviolet rays), heat, oxygen and ozone, flame retardants, lubricants, and
The effects can be further enhanced by incorporating additives such as fillers, reinforcing agents, impact modifiers (for example, metal salts of carboxylic acids), colorants, antistatic agents, and mold release agents. , these formulations are also encompassed by the present invention.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

one! Example 1 The present invention will be described in detail below, but it goes without saying that the scope of the present invention is not limited to these Examples.

Production of ring-opening polymer> Into a 50-liter autoclave completely purged with nitrogen, 25-liters of 1,2-dichloroethane, 15M of 5-cyano-bicyclo(2,2,l)-hebutene-2 (purse-string material) as
125 mol) and diethylaluminum chloride (
1.0 mol/cross at a concentration of 1.0 mol/cross
100 ml of 2-dichloroethane solution was charged and stirred at room temperature until uniform.

Next, the temperature of the reaction system to which 300 m of a toluene solution containing phenylethoxycarbene pentacarponyl tungsten at a concentration of 0.1 mol/cross was added as a carbene complex was raised to 75°C, and while stirring at this temperature for 60 minutes, Polymerization was carried out. After completion of the polymerization, 1 containing about 1.0% by weight of 2.6-di-tert-butyl-P-cresol,
The polymerization was stopped by adding about 5 portions of a mixed solution of 2-dichloroethane and methyl alcohol (approximately 4=1 in volume), and the resulting polymer was precipitated using a large amount of methyl alcohol. After filtration, the polymer was thoroughly washed with methyl alcohol, and then dried at about 50° C. under reduced pressure for about 24 hours. The result was 11.7kg.
A polymer was obtained.

Injection molding of a disc> The obtained ring-opening polymer was molded using a 30III 11φ two-piece extruder in the same direction manufactured by Ikegai Steel Co., Ltd. (cylinder temperature set at 240°C).
) It became Peleft.

The pellets were molded into a thin disk shape using the following injection molding machine.

・Molded product 1.2mm thick x 120mm diameter disk gate is a center direct gate (gate j) ≦ 6111mφ)・
Injection molding machine Sumitomo Heavy Industries Cycap MII [+85/75 Mold clamping pressure 75T (IN ・Molding conditions Mold temperature 100 (° cm' Cycle Injection (including holding pressure) 5 (Sea) Cooling 10 (sec) Active energy ray !'!q irradiation Using a curtain beam type electron beam irradiation device, electron beam was irradiated under the following conditions. .

Accelerating voltage: 300 KeV Electron beam current: 72 mA Dose capacity: 20 Mrad/sec Line speed: 24 m/win Number of reciprocations: 10 times Total vj amount: 50 Mrad Performance evaluation> The performance of the optical disk substrate obtained by the above method was evaluated. did.

Values at 780 nm and 830 nm are shown using an O light transmittance spectrophotometer.

Measurement was performed using an ellipsometer using an O-birefringent He--Ne laser as a light source. The values were expressed in retardation and converted to double-pass values.

O Heat Resistance CHDT) Tested according to the method of ASTM D-648. The load is 68 ps i .

O water absorption rate Tested using the ASTM D-570 method.

0 Chemical Resistance Visually observe surface changes when immersed in acetone and methylene chloride.

O...No change ×...Change 01
ll)l Impact strength A 200g steel ball is dropped from a height of 50CI11...
...Wallace ×...Cracks and warping Example 2 In Example 1, 5-cyano-bicyclo[2゜2,l
]-Hebutene-2 was replaced with 5-methyl-5-methoxycarbonyl-bicyclo(2,2,l)-hebutene-2 to obtain a ring-opened polymer, and the same method was used to obtain an optical disc. Ta.

Example 3 5-cyano-bicyclo[:2.2. l]-to]butene and 5-bromo-6-methyl-bicyclo[2゜2.1
]-hebutene-2 at a molar ratio of 7:3, the ring-opened polymer was formed into an optical disk in the same manner as in Example 1, and irradiated with an electron beam.

Example 4 5.6 bistalolomethyl-bicyclo(2,2,1)-hebutene-2 and 5-phenyl-bicyclo(2,2,1)-
The molar ratio with hebutene-2 is 6:4 ring-opening aggregate 100
0.01 part by weight of benzoin isopropyl ether per part of hair was mixed in an extruder to form pellets. An optical disc was obtained by injection molding in the same manner as in Example 1. This molded body was irradiated with ultraviolet light. The conditions are shown below.

Output: 3 Light source: Microwave-excited metal halide lamp Irradiation amount: 50 J/cm' Comparative Example 1 An optical disc was obtained by injection molding using polycarbonate resin.

Comparative Example 2 An optical disc was obtained by injection molding using polymethyl methacrylate resin.

Comparative example 3 In Example 1, the electron beam was not irradiated.

Comparative example 4 In Example 4, no ultraviolet rays were irradiated.

The performance of the optical disc substrates obtained in Examples 1 to 4 and Comparative Examples 1 to 4 was evaluated, and the results are summarized in Table 1.

(Left below) As described above, the optical disc manufactured by the present invention has a better balance of properties as an optical disc than PC, PMMA, etc., and is further cross-linked with active energy rays. Therefore, the chemical resistance is also improved, and a good optical disc substrate is provided.

Special a’U applicant Showa Denko Co., Ltd. Representative Patent Attorney: Kikuchi Karu

Claims (1)

[Claims] 1. (i) at least one polar group selected from the group consisting of a nitrile group, an ester group, a chlorine atom, an acid anhydride group, and an imide group, or a compound containing a large number of carbon atoms containing the polar group; a norbornene derivative having both 20 hydrocarbon residues, or (ii) the norbornene derivative and at most 50 mol% of a cycloolefinic compound or an aromatic hydrocarbon group;
and a norbornene derivative having at least one group selected from the group consisting of an ether group, an amide group, and a bromine atom. An optical disc substrate characterized by irradiating a disc with active energy rays.