JPH01315459A - Optical molding material - Google Patents

Abstract

PURPOSE:To obtain an optical molding material suitable as optical disc, etc., having excellent moldability, especially excellent mold release characteristics, mold transcription, heat resistance, etc., by blending a polycarbonate having a specific average molecular weight with specific amounts of phosphorous acid, alpha-monoalkylglyceryl ether, etc. CONSTITUTION:100 pts.wt. polycarbonate resin having 12,000-23,000 viscosity average molecular weight is blended with (A) 0.0005-0.01 pts.wt., preferably 0.001-0.005 pts.wt. phosphorous acid, (B) 0.005-0.05 pts.wt. alpha-monoalkylglyceryl ether shown by the formula (R is 8-22C saturated or unsaturated straight-chain or branched-chain alkyl) and (C) 0.005-0.2 pts.wt., preferably 0.01-0.15 pt.wt. ester of 10-30C saturated fatty acid and <=30C mono- or polyhydric alcohol in a ratio of 0.02-0.2 pt.wt. sum of the components B and C.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a polycarbonate resin molding material that has excellent heat resistance and moldability, and is suitable for manufacturing optical molded products such as optical discs, lenses, and prisms. .

[Conventional technology and its problems]

Recently, polycarbonate resin has been improved due to its transparency, heat resistance,
Taking advantage of its characteristics such as hydrolysis resistance and dimensional stability, it has become widely used as a substrate material for lenses and optical information disks, etc. Along with this, improvements in thermal stability and mold release properties have become important issues. It has become.

Conventionally, organic phosphites have been the main stabilizer for polycarbonate in practical use, but it is well known that this hydrolyzate accelerates the decomposition of polycarbonate itself. When polycarbonate resin is hydrolyzed, its decomposition products precipitate into the molded product as fine white spots, blocking the passage of light rays.

Phosphonite-based compounds that have been proposed as non-organophosphites have similar hydrolyzability, and organic phosphines and organic phosphine oxides have the disadvantage of insufficient improvement in heat resistance stability, and are difficult to mold. When the product is heated, it appears as a result of significant yellowing.

On the other hand, optical molded products, especially optical discs and lenses, are manufactured by injection molding, but when they are released from the mold,
If the mold release resistance is large, it will cause warping of the molded product and optical distortion, so it is necessary to use a mold release agent. Particularly in the case of optical discs, it is necessary to accurately transfer irregularities of 1 or less on the stand bar, and this is largely dependent on the performance of the mold release agent.

Paraffin, silicone oil, fatty acids, fatty acid esters, fatty acid partial esters (particularly fatty acid monoglycerides), and the like are conventionally known as mold release agents for polycarbonate resins. Among these, fatty acids and fatty acid monoglycerides have excellent mold release properties when used in small amounts, but these
/90% RH), it promotes hydrolysis of the polycarbonate resin, so it is not preferable to add more than 0.01 part by weight per 100 parts by weight of the polycarbonate resin. However, from the standpoint of mold releasability, this amount or more, for example 0
．． It is preferable to add about 0.04 parts by weight.

Polycarbonate resin, paraffin, silicone oil, fatty acid ester, etc. have insufficient mold release effect, and polycarbonate resin 1
Although it is preferable to add 0.2 parts by weight or more to 0.00 parts by weight, such an addition amount has the disadvantage that flow marks are likely to occur on the surface of the molded product.

[Problem that the invention seeks to solve]

The present invention has excellent moldability, particularly mold releasability and transferability, and
The object of the present invention is to provide an optical polycarbonate resin molding material that has excellent heat resistance and hydrolysis resistance.

[Means for solving problems]

The present invention has a viscosity average molecular weight of 12.000 to 23.00.
(1) per 100 parts by weight of polycarbonate resin of
, 0.0005 to 0.01 parts by weight of phosphorous acid, (2), 0.005 to 0.05 parts by weight of α-monoalkyl glyceryl ether of the following general formula (1), and general formula (1)
: RO-C112CH(DH)CHI(011)
... (1) (R in the formula represents a saturated or unsaturated linear or branched alkyl group having 8 to 22 carbon atoms).

(3) Ester of saturated fatty acid having 10 to 30 carbon atoms and monohydric or polyhydric alcohol having 30 or less carbon atoms 0,005
-0.2 parts by weight of an optical molding material, furthermore, the total amount of α-monoalkyl glyceryl ether (2) of the general formula (1) and the ester (3) is polycarbonate. The object of the present invention is to provide a molding material having extremely excellent thermal stability and mold releasability at a content of 0.02 to 0.2 parts by weight per 100 parts by weight of resin.

The configuration of the present invention will be explained below.

The polycarbonate resin of the present invention is a homo- or copolycarbonate resin obtained by the reaction of dihydric phenol with a carbonate precursor such as phosgene or diphenyl carbonate, a further branched resin, or a resin with a long-chain alkyl group introduced at the end. The average molecular weight of things etc. is 12.000-23
．． 000; modified polycarbonate resin obtained by using bisphenol or vinylphenol having a carbon-carbon unsaturated double bond as a comonomer or terminal capper, grafted with styrene, etc., and terephthalic acid as part of the phosgene. Examples of materials that can be used include those that use chloride or isophthalic acid chloride and partially have an ester bond, or those that are obtained by graft polymerizing a polycarbonate resin to modified polystyrene that uses a phenolic hydroxyl group as a comonomer. .

Here, as the dihydric phenol, 2.2-bis(4-
hydroxyphenyl)propane (=bisphenol A)
, bis(4-hydroxyphenyl)methane, 1,2-his(4-hydroxyphenyl)ethane, 2,2-bis(
4-hydroxyphenyl)butane, 1,1-bis(4-
Hydroxyphenyl)-1-phenylmethane, 1゜1-
Bis(4-hydroxyphenyl-1,1-diphenyl)
Methane, 1,1-bis(4-hydroxyphenyl)cyclohexane, bis(4-hydroxyphenyl)ether, bis(4-hydroxyphenyl)sulfide, bis(
Examples include 4-hydroxyphenyl) sulfone, and those in which a lower alkyl group or a halogen atom is substituted for these phenyl groups, and bisphenol A is particularly representative.

(1) of the present invention to be blended with the above polycarbonate resin
The phosphorous acid suppresses the heat resistance of the resin, especially the molecular weight reduction during molding, and does not promote the decomposition of polycarbonate even in high temperature and humid environments. this is,
When phosphorous esters are used, their decomposition products are
This is different from promoting the decomposition of polycarbonate.

The amount of phosphorous acid (1) added is 0.0005 to 0.01 parts by weight, particularly 0.0005 to 0.01 parts by weight, per 100 parts by weight of the polycarbonate resin.
001 to 0.005 parts by weight is suitable, and 0.0005 parts by weight
If it is less than 0.01 part by weight, the decomposition prevention effect is insufficient.
Using more than the weight part will actually accelerate decomposition.

Examples of the method for adding phosphorous acid (1) include a method in which powder is mixed with polycarbonate resin and extruded, and a method in which it is added as an aqueous solution to polycarbonate resin and extruded.

Additive components (2) and (3) of the present invention are mold release agents that improve the mold release property during injection molding and improve the transferability of ultrafine irregularities of the mold, and the component (2) and the component (3) improves the mold release effect more when used in combination than when used alone, and as a result, a molding material with good mold release properties can be obtained with a smaller amount added. When a recording film is attached to a molded substrate, such as an optical disk, by sputtering or vapor deposition, the adhesion strength between the substrate and the recording film is extremely important for the long-term reliability of the optical disk. This is because it is undesirable because it has side effects such as promoting adhesion strength and hydrolysis. In the present invention, the total amount of component (2) and component (3) as mold release agents is 0.0 per 100 parts by weight of polycarbonate resin.
A range of 2 to 0.2 parts by weight is preferable from the viewpoint of balance between thermal stability and mold releasability.

First, component (2) is represented by the above general formula (1) and has a primary, secondary, or tertiary alkyl group having 8 to 22 carbon atoms. This α-monoalkylglyceryl ether is produced by synthesizing alkylglycidyl ether from alcohol and epihalohydrin and hydrolyzing it as shown in the following formula; Prior to this hydrolysis, the glycidyl ether is first reacted with a carbonyl compound. 4-alkoxymethyl-1,
3-dioxolane and hydrolyze it + H,0(
hydrolysis) → RO-C1,CI (DI() CI (O
H).

Specifically, n-octylglyceryl ether, n-decylglyceryl ether, laurylglyceryl ether,
Those with straight fatty chains such as myristylglyceryl ether, palmitylglyceryl ether, stearylglyceryl ether, alaxylglyceryl ether, behenylglyceryl ether, oleylglyceryl ether; 2-ethylhexylglyceryl ether, 2-hexyldecylglyceryl ether, tart -Octylglyceryl ether, tart-dodecylglyceryl ether and the like having a branched fatty chain are exemplified.

Among these, particularly preferred compounds are palmityl glyceryl ether, stearyl glyceryl ether, and behenyl glyceryl ether.

The α-monoalkyl glyceryl ether of component (2) is
Like partial esters of polyhydric alcohols having hydroxyl groups in the molecule, they provide good mold release properties when added in small amounts, but they have higher heat resistance and less coloring than partial esters of fatty acids. The amount added is preferably 0.005 to 0.05 parts by weight, and 0.0 parts by weight per 100 parts by weight of the polycarbonate resin.
If it is less than 0.05 parts by weight, the effect is small, and if it is used in excess of 0.05 parts by weight, white spots are likely to occur due to hydrolysis of the polycarbonate resin when the molded product is left in a high temperature and humid environment for a long time. .

Next, component (3), an ester of a saturated fatty acid having 10 to 3 carbon atoms and a monohydric or polyhydric alcohol having 30 or less carbon atoms, is a full ester having no alcoholic hydroxyl group. These fatty acid esters are known as ester waxes that are found in synthetic products as well as natural products such as plants, animals, insects, and minerals, and specifically include butyl stearate, stearyl stearate, and behenyl stearate. Synthetic products such as behenate, methyl laurate, isopropyl palmitate, 2-ethylhexyl stearate, pentaerythritol tetrastearate, pentaerythritol tetrabehenate, and long-chain fatty acid esters are the main components, and the purity of these components High! 6 etc. The amount added is 0 per 100 parts by weight of polycarbonate resin.
．． 0.005 to 0.2 parts by weight, particularly 0.01 to 0.15 parts by weight are preferred.

Furthermore, in the present invention, the above-mentioned components (1), (2) and (
In addition to the stabilizers and mold release agents mentioned in 3), hindered phenol antioxidants, colorants, ultraviolet absorbers, etc. can be used. Generally, these additives are mixed with a polycarbonate resin mixture and then melted and extruded using an extruder, or they are added and mixed into a polycarbonate resin solution, and then the solvent is distilled off to take out the polycarbonate resin. You can also do it.

〔Example〕

The present invention will be explained below with reference to Examples.

In addition, %, parts, etc. in Examples etc. are based on weight unless otherwise specified, and the measurement method was as follows.

Measurement of mold release force.

7.8 oz injection molding machine (manufactured by Mitsubishi Heavy Industries ■, 5
15-150 MST type), resin temperature 280℃,
A molded product in the shape of a pot (bottom inner diameter 60mm, top inner diameter 70mm, depth 70mm, wall thickness 3mm) is molded at a mold temperature of 80°C with an internal mold pressure of 800 to 805 kg/cnf, and this molded product is released from the mold. The resistance value is read with a pressure sensor attached to the protruding bottle.

Measurement of molecular weight changes.

The pellets are dried at 120° C. for 4 hours, and approximately 2 g is placed in a test tube and heated at 370° C. for 20 minutes + under a stream of N2. Changes in molecular weight before and after heating are measured using a flow tester (manufactured by @Kinsei Seisakusho,
Temperature 280℃, load 160kg/caf, orifice 1
mmΦxlQmmL) was used as a guideline for molecular weight change.

Incidentally, the smaller the change in Q value before and after heating, the smaller the molecular weight change, and the better the thermal stability.

Appearance and long-term moisture resistance test.

Using a 3.0 oz injection molding machine (manufactured by Sumitomo Heavy Industries ■, Disc 5M3 type), the resin temperature was 320°C and the mold temperature was 105°C, and the pellets were molded into a disc with a thickness of 1.2 mm and a diameter of 130 mm. Visually observe the color of the board, burn marks, flow marks, and the presence or absence of soot-like appearance (external appearance).

In addition, after putting this disk in an environmental tester at 80°C and 90% RH and aging it for 500 hours, the 501 generated in the disk
The number of white spots above is read using an optical microscope.

Examples 1 to 5 and Comparative Examples 1 to 7 Caustic soda aqueous solution of bisphenol A and methylene chloride (
=MC) was stirred at 20°C while phosgene was introduced.

Next, p-tert-butylphenol and triethylamine were added, and the mixture was reacted for 1 hour with strong stirring, after which a methylene chloride solution of the reaction product mixture was separated and washed repeatedly with water.

Add 2 parts of n-hebutane (=nH) to 100 parts by volume of this solution.
5 parts by volume were added and mixed, the mixed solution was dropped into warm water, and then the temperature was raised to 100°C and the solvent was distilled off to obtain a slurry of polycarbonate powder.

This powder was filtered out and dried at 120°C for 8 hours to obtain polycarbonate with a viscosity average molecular weight of 15.000.

This polycarbonate powder was mixed with the additives listed in Table 1 and extruded at a resin temperature of 250 to 270 DEG C. to form pellets to obtain a molding material.

Table 1 shows the results of measurements of mold release resistance, molecular weight change, appearance, and long-term moisture resistance tests using the above pellets.

[Operation and effects of the invention]

As mentioned above, the polycarbonate resin optical molding material of the present invention has little occurrence of burns even when molded at 300 to 380°C, and has extremely excellent mold releasability. The optical distortion is extremely small.

Furthermore, even when the product is forced to be used in a high-temperature, high-humidity environment, there is little molecular weight reduction due to hydrolysis, and there is little occurrence of white spots, which is an extremely serious problem for optical molded products.

Patent applicant: Mitsubishi Gas Chemical Co., Ltd.

Claims (1)

[Claims] 1. Per 100 parts by weight of polycarbonate resin having a viscosity average molecular weight of 12,000 to 23,000, (1), 0.0005 to 0.01 parts by weight of phosphorous acid, (2)
, 0.005 to 0.05 parts by weight of α-monoalkylglyceryl ether of the following general formula (1), and general formula (1)
:RO-CH_2CH(OH)CH_2(OH1)...
-(1) (R in the formula represents a saturated or unsaturated linear or branched alkyl group having 8 to 22 carbon atoms). (3) An optical molding material containing 0.005 to 0.2 parts by weight of an ester of a saturated fatty acid having 10 to 30 carbon atoms and a monohydric or polyhydric alcohol having 30 or less carbon atoms. 2 The total addition amount of the α-monoalkyl glyceryl ether (2) of the general formula (1) and the ester (3) is 0.02 to 0.2 per 100 parts by weight of the polycarbonate resin.
The optical molding material according to claim 1, which is in parts by weight.