JPH0713128B2 - Polyester or polyester carbonate resin - Google Patents

Description

TECHNICAL FIELD The present invention relates to a novel polyester or polyester carbonate resin.

The polyester or polyester carbonate resin provided by the present invention has excellent properties such as low birefringence and high heat resistance, and is suitable for optical recording media such as optical discs and optical cards; lenses, prisms, diffraction gratings, etc. Suitable for materials of optical molded products such as optical elements.

[Conventional technology]

In recent years, transparent resins excellent in various properties have been required as materials for molded articles in various fields such as optical parts and automotive parts. Among optical recording media such as optical disks and optical cards, write-once and erasable types that allow users to record information have appeared, and with the development of such recording methods, there are demands for various characteristics of the substrate material. The level of is increasing. Particularly required are three characteristics: low water absorption (low water absorption warpage), low birefringence, and high heat resistance. Currently, glass and plastic materials are used as the base material,
Glass has the disadvantages of low mass productivity, high cost, heavy weight, and fragility, and plastic materials that do not have such shortcomings are currently the mainstream of substrate materials. Further, for lenses such as concave / convex lenses and Fresnel lenses, and optical elements such as diffraction gratings, plastic materials are becoming more predominant than glass for the same reasons as in optical recording media as the applications are expanded.

Polymethylmethacrylate (hereinafter referred to as PMMA) and bisphenol A polycarbonate (hereinafter referred to as
Abbreviated as PC). Although PMMA has a very low birefringence, it has a high water absorption (moisture absorption) property, and it has a drawback that it tends to be warped or deformed due to water absorption, which easily causes deterioration of optical characteristics. In particular, when PMMA is used as a material for an optical recording medium composed of a single substrate such as a digital audio disk, faithful reproduction of information may be impossible. Further, the optical recording medium using PMMA as a base material has some problems in heat resistance. On the other hand, PC has low water absorption, almost no warpage due to water absorption, and there is no problem in heat resistance, but it has the drawback of large birefringence. It is possible to suppress the birefringence below the required level by controlling the molding conditions with high precision for digital audio disks and small diameter lenses, but for the 30 cm diameter laser vision and large diameter lenses It is extremely difficult to control with high precision.

Conventionally, the glass transition temperature of a polyester having a norbornane skeleton, a perhydrodimethanonaphthalene skeleton, or a perhydrotrimethanoanthracene skeleton becomes higher in the order of this skeleton, and these polyesters are higher than those having no such skeleton. Have been reported to have a high glass transition temperature [Journal of Polymer Science: Polymer Chemistry: Polymer Chemistry Ed.
mstry Edition), vol. 10, p. 3191 (1972)], and polyester having the above skeleton has excellent dimensional stability and is known to be used as a base material for photographic film (US Defense Patent). No. 896,033).

[Problems to be Solved by the Invention]

As described above, PMMA conventionally used as a transparent optical material has a drawback that it tends to warp or deform due to water absorption, and has insufficient heat resistance, and PC has a large birefringence. There is a drawback that.

Therefore, an object of the present invention is to provide a novel polyester or polyester carbonate resin having a high glass transition temperature, excellent heat resistance, low birefringence and excellent transparency, and warpage due to water absorption and little deformation. Especially.

[Means for Solving the Problems]

According to the present invention, the above objects are represented by the following formulas (I) and (I
Structural units represented by I), (III), (IV) and (V) (In the formula, m represents 0, 1 or 2.) (In the formula, A represents a divalent saturated aliphatic hydrocarbon group, a saturated alicyclic hydrocarbon group or an aromatic hydrocarbon group.) (In the formula, n represents 0, 1 or 2.) (V): O-B-O (In the formula, B is a divalent saturated aliphatic hydrocarbon group, a saturated alicyclic hydrocarbon group or an aromatic group. Which represents a hydrocarbon group), and the mole fraction of the structural unit (I) and the structural unit (II)
Of the structural unit (III) and the structural unit (III) are substantially equal to the total of the structural unit (IV) and structural unit (V). The mole fraction and the mole fraction of the structural unit (IV) are each 5 mol% or more,
And to provide a polyester or polyester carbonate resin having a number average molecular weight of 10,000 to 100,000 and having a composition in which the sum of the mole fractions of the structural unit (I) and the structural unit (IV) is 50 to 95 mole%. Is achieved by

The above structural unit will be described in detail.

The structural unit (I) is specifically as follows.

The heat resistance of the resin having the structural unit (I) is better when m in the general formula (I) is larger. Therefore, the resin having m of 1 or 2 may be used. preferable.

In the structural unit (II), A in the general formula (II) has 1 to 1 carbon atoms.
It is preferably a divalent saturated aliphatic hydrocarbon group having 20 carbon atoms, a divalent saturated alicyclic hydrocarbon group having 3 to 20 carbon atoms or a divalent aromatic hydrocarbon group having 6 to 20 carbon atoms. However, it is a divalent saturated aliphatic hydrocarbon group having 1 to 12 carbon atoms, a divalent saturated alicyclic hydrocarbon group having 4 to 15 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 12 carbon atoms. The case is more preferable.

Preferred examples of the structural unit (II) are shown below.

(I) When A represents a divalent saturated aliphatic hydrocarbon group: (Ii) When A represents a divalent saturated alicyclic hydrocarbon group: (Iii) When A represents a divalent aromatic hydrocarbon group: Of the above structural units (II), the following structural units particularly impart excellent heat resistance to the resin of the present invention.

Further, the following structural units provide the resin of the present invention with the best heat resistance.

Regarding the resin of the present invention having the structural unit (II) belonging to the above (iii), when this resin is used for an application requiring a low birefringence, such as a substrate for a magneto-optical recording medium. Requires that the mole fraction of its structural units be kept low.

Both the structural unit (I) and the structural unit (II) are derived from the corresponding dicarboxylic acid or its derivative such as phenyl ester, alkyl ester, cycloalkyl ester, acid chloride and the like. It is preferable to use a phenyl ester or an alkyl ester because of the ease of polymerization when producing the resin of the present invention.

The structural unit (III) is derived from a carbonic acid derivative such as diphenyl carbonate, dialkyl carbonate, dicyclocarbonate or phosgene. It is preferable to use diphenyl carbonate or dialkyl carbonate because of the ease of producing the resin of the present invention.

The structural unit (IV) is specifically as follows.

The heat resistance of the resin having the structural unit (IV) is better when n in the general formula (IV) is larger. Therefore, it is preferable that the resin has n of 1 or 2, that is, has the following structure. .

In the structural unit (V), B in the general formula (V) has 1 to 1 carbon atoms.
It is preferably a divalent saturated aliphatic hydrocarbon group having 20 carbon atoms, a divalent saturated alicyclic hydrocarbon group having 3 to 20 carbon atoms or a divalent aromatic hydrocarbon group having 6 to 20 carbon atoms. However, it is a divalent saturated aliphatic hydrocarbon group having 1 to 12 carbon atoms, a divalent saturated alicyclic hydrocarbon group having 4 to 15 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 12 carbon atoms. The case is more preferable. In addition,
The saturated alicyclic hydrocarbon group also includes those having a spiro ring which may contain an oxygen atom.

Preferred examples of the structural unit (V) are shown below.

(B) When B represents a divalent saturated aliphatic hydrocarbon _{group: -OCH 2 CH 2 O -,} - OCH 2 CH 2 CH 2 O -, - OCH 2 CH 2 CH 2 CH 2 O
-, (B) When B represents a divalent saturated alicyclic hydrocarbon group: (C) When B represents a divalent aromatic hydrocarbon group: Of the above structural units (V), particularly the following structural units impart excellent heat resistance and mechanical strength to the resin of the present invention.

-OCH ₂ CH ₂ O-, -OCH ₂ CH ₂ CH ₂ CH ₂ O-, Further, the following structural units give the resin of the present invention the best heat resistance and mechanical strength.

-OCH ₂ CH ₂ O-, -OCH ₂ CH ₂ CH ₂ CH ₂ O-, Regarding the resin of the present invention having the structural unit (V) belonging to (C) above, when this resin is used for applications requiring low birefringence, such as a substrate for a magneto-optical recording medium. Requires that the mole fraction of its structural units be kept low.

Both structural unit (IV) and structural unit (V) are derived from the corresponding dihydroxyl compound.

In the resin of the present invention, the structural unit (I) and the structural unit (II) are bonded to the structural unit (IV) or the structural unit (V) through an ester bond. Further, the structural unit (III) is bonded to the structural unit (IV) or the structural unit (V) by a carbonate bond.

In the resin of the present invention, the molar fraction v of the structural unit (I) and the molar fraction y of the structural unit (IV) are each 5 mol% or more, and their sum (v + y) is 50 to 95 mol%. . The sum of mole fractions (v + y) is preferably in the range of 60 to 95 mol%, more preferably 70 to 90 mol%. When the mole fraction is less than 50 mol%, the resin may not have sufficient heat resistance, and when it exceeds 95 mol%, the resin has sufficient heat resistance, but its mechanical strength is high. Is low and neither is practical.
The molar fraction w of the structural units (II), (III) and (V),
x and z satisfy the equations v + w + x = 50 and y + z = 50.

The resin of the present invention has a number average molecular weight (in terms of polystyrene) determined by gel permeation chromatography (hereinafter, abbreviated as GPC) of 10,000 to 100,000. The number average molecular weight of the resin of the present invention is 1
Preferably in the range of 5,000-80,000, 20,000-8
More preferably, it is in the range of 0,000. A resin having a number average molecular weight of less than 10,000 is brittle and does not have sufficient practical strength, and a resin having a number average molecular weight of more than 100,000 is difficult to manufacture.

The resin of the present invention can be produced by a known method. Known methods are, for example, dephenol and / or dealcoholization reactions from diphenyl and / or dialkyl esters of dicarboxylic acids and diphenyl carbonates and / or mixtures of dialkyl carbonates and dihydroxyl compounds, phosgene and dicarboxylation. Of a suitable catalyst, such as a dehydrochlorination reaction from a mixture of a compound with a dihydroxyl compound, a dealkalium chloride reaction from a mixture of phosgene with a dicarboxylic acid chloride and an alkali metal salt of a dihydroxyl compound, etc. It is carried out in the presence. As a reaction mode, a melting method, a solution method or the like can be adopted depending on the kind of the reaction, but the melting method is preferable from the viewpoint of easy reaction.

The case of producing the resin of the present invention by a melting method will be described below. Examples of the catalyst include tetraalkyl orthotitanate, zinc acetate, antimony oxide, germanium oxide; various metal alkoxides such as sodium methoxide and potassium t-butoxide; alkali metals such as lithium and sodium; lithium hydride and sodium hydride. Alkali metal hydrides; alkali metal hydroxides such as lithium hydroxide and sodium hydroxide; metal halides and the like. When an aromatic dihydroxyl compound is used as the raw material compound, it is preferable to use an alkali metal, an alkali metal hydride or an alkali metal hydroxide as a catalyst because of its high reactivity. The amount of the catalyst used is not particularly limited, but usually 0.
It is in the range of 0001 to 1 mol%. When the amount of the catalyst used is small, the reaction rate is extremely reduced, and when the amount of the catalyst used is too large, the water absorption rate of the obtained resin may be increased or coloring may be caused. The polycondensation reaction is carried out by stirring the raw material compound while heating in the presence of a catalyst in an atmosphere of an inert gas such as nitrogen, argon or carbon dioxide, and distilling the generated alcohol or phenol.
The reaction temperature will differ depending on the starting compounds and the boiling points of the alcohol or phenol generated and the reaction rate required, but it is usually in the range of 150 to 300 ° C. In the latter half of the reaction, the system is depressurized as necessary to drive the reaction. The pressure at this time is in the range of 0.001 to 100 mmHg. After the reaction is completed, the obtained resin is extruded in a strand form from the reactor and then pelletized by a pelletizer, or taken out in a lump form and pulverized.

The resin of the present invention produced as described above has a high glass transition temperature, excellent heat resistance, low birefringence, and excellent transparency. Further, the resin of the present invention does not warp or deform due to water absorption.

The resin of the present invention can be molded by any known method, for example, a melt molding method such as press molding, extrusion molding, injection molding, and injection compression molding. Alternatively, the resin of the present invention may be dissolved in a suitable solvent to form a film by the cast method. In the case of melt molding, the resin temperature is usually set to 200 to 400 ° C, and the mold temperature is set to 40 to 150 ° C. At the time of molding, a heat stabilizer, a light stabilizer, an antistatic agent, a lubricant, an inorganic or organic filler, a dye, a pigment or the like may be added to the resin of the present invention as required.

The resin of the present invention may be formed into a flat plate or a simple shape and then laminated with an inorganic or organic material, may be formed into a complicated shape by adhesion or fusion, and may be subjected to higher-order processing such as embossing on the surface. It is also possible to apply.

When the resin of the present invention is used, for example, as a material for a read-only optical recording medium substrate, first, the resin of the present invention is molded by injection molding or the like using a mold in which grooves, signals, etc. are recorded. To get A metal such as aluminum is formed on this substrate by a method such as vacuum deposition on the information surface, and then a protective polymer layer is formed, or two information surfaces each having a metal surface are formed on the information surface. to paste together. The information recording layer may be provided by a 2P method using a photocurable resin on a flat substrate made of the resin of the present invention.
The information recording layer can also be formed by providing a thin film of an inorganic material such as tellurium oxide or a terbium-iron-cobalt alloy or an organic material such as a cyanine dye on the surface of the molded substrate.

The resin of the present invention can be used for the following applications by taking advantage of the above excellent properties.

Lighting equipment parts Various signboards Glass substitutes in fields such as windows and windshields Substrates for various display devices such as liquid crystals Various lenses such as concave / convex lenses and Fresnel lenses used for eyeglasses, cameras, magnifiers, video projectors, etc. Optical disc player pick-up Various optical elements such as a spectroscopic element, a diffraction grating prism such as an optical low-pass filter, an optical waveguide, a beam splitter, etc. A substrate for an optical recording medium such as an optical fiber optical disc and an optical card [Examples] Will be specifically described. In addition,
The physical property values were measured according to the following methods.

Number average molecular weight: determined by GPC (polystyrene conversion).

Glass transition temperature: Differential thermal analysis (in nitrogen, heating rate
10 ° C / min).

Light transmittance: The transmittance of light having a wavelength of 400 nm, 600 nm and 800 nm of a sample molded to a thickness of 2 mm by hot pressing was measured by a spectrophotometer.

Birefringence (retardation): diameter 40mm, thickness 6mm
The sample molded into 1. was rolled to a thickness of 1 mm by hot pressing, and measured at a point 30 mm from the center using a polarization microscope (wavelength 589 nm).

Surface hardness: determined by a pencil hardness test (JIS K5400).

Saturated water absorption rate: Saturated water absorption rate: Measured by obtaining the weight increase rate when no weight increase due to water absorption was observed in distilled water at 23 ° C.

Water absorption warp: Aluminum was vapor-deposited to a thickness of 1000 Å on one surface of a plate-like sample having a thickness of 2 cm × 10 cm × 2 mm and immersed in distilled water at 23 ° C to determine the maximum value of the warpage as the water absorption warpage.

Izod impact strength: Measured in accordance with JIS K7110 (with notch), based on the Izod impact strength of bisphenol A polycarbonate, those with the same degree of Izod impact strength are aligned, and higher Izod impact strength Those having the above were evaluated as good, and those having a low Izod impact strength were evaluated as poor.

Example 1 A one-volume three-necked flask equipped with a stirrer, a nitrogen gas inlet and a cooling tube was charged with 139 g (0.50 mol) of dimethyl perhydro-1,4: 5,8-dimethanonaphthalene-2,3-dicarboxylate. Dimethyl trans-1,4-cyclohexanedicarboxylate 100 g (0.50 mol), perhydro-1,4: 5,8-dimethanonaphthalene-2,3-dimethanol 222 g (1.0 mol) and tetrabutyl orthotitanate 0.34 g ( 1 mmol) was charged, and the mixture was heated to 200 ° C. in an oil bath in a nitrogen stream and stirred for 30 minutes. Then, at 230 ℃ for 50 minutes, 250 ℃
After stirring for 80 minutes, reduce the pressure in the system to 1.0 mmHg, and stir for another 60 minutes under this reduced pressure to give 380 g of a pale yellow transparent resin.
Got The ¹ H NMR spectrum (90 MHz, in deuterated chloroform, based on tetramethylsilane) of this resin is shown in FIG.

Table 2 shows the measurement results of various physical properties of the obtained resin.

Examples 2 to 8 Various resins were obtained by carrying out the reaction in the same manner as in Example 1 except that the raw material compound and / or the charged amount thereof was changed. However, when diphenyl carbonate was used as a part of the raw material compound, lithium hydride was used instead of 0.34 g (1 mmol) of tetrabutyl orthotitanate.
8.0 mg (1 mmol) was used. The raw material compounds used and the amount charged are shown in Table 1.

Table 2 shows the measurement results of various physical properties of the resins obtained in Examples 2 to 3. In the same table, as Comparative Example 1, the physical properties of bisphenol A polycarbonate are shown.

The resins obtained in Examples 4 to 8 also have a glass transition temperature of 130 ° C.
Higher than above, retardation is low below about 5 nm,
It had good physical properties.

The resins obtained in Examples 1 to 8 all had a low saturated water absorption rate of 0.4% or less and a small water absorption warpage of 0.1 mm or less.
Further, the surface hardness was as high as H or higher.

[Advantages of the Invention] The present invention provides a polyester or polyester carbonate resin having the following features and suitably used for various applications such as optical molded articles.

 It has excellent transparency.

 High glass transition point and good heat resistance.

 High surface hardness of H or higher.

Saturated water absorption is as low as 0.4% or less, causing warpage due to water absorption.
Almost no deformation occurs.

The birefringence of the molded product is very small, about 1/4 or less that of bisphenol A polycarbonate.

[Brief description of drawings]

FIG. 1 shows ¹ H NM of the polyester resin obtained in Example 1.
This is the R spectrum.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G11B 7/24 526 H 7215-5D

Claims (1)

[Claims] 1. The following formulas (I), (II), (III) and (IV)
And structural units represented by (V) (In the formula, m represents 0, 1 or 2.) (In the formula, A represents a divalent saturated aliphatic hydrocarbon group, a saturated alicyclic hydrocarbon group or an aromatic hydrocarbon group.) (In the formula, n represents 0, 1 or 2.) (V): O-B-O (In the formula, B is a divalent saturated aliphatic hydrocarbon group, a saturated alicyclic hydrocarbon group or an aromatic group. Which represents a hydrocarbon group), and the mole fraction of the structural unit (I) and the structural unit (II)
Of the structural unit (III) and the structural unit (III) are substantially equal to the total of the structural unit (IV) and structural unit (V). The mole fraction and the mole fraction of the structural unit (IV) are each 5 mol% or more,
A polyester or polyester carbonate resin having a number average molecular weight of 10,000 to 100,000 and having a composition in which the sum of the mole fractions of the structural unit (I) and the structural unit (IV) is 50 to 95 mole%.