JP6773030B2 - Polycarbonate resin film - Google Patents

Description

The present invention relates to a polycarbonate resin film made of a polycarbonate resin composition, a polarizer protective film using the same, and a polycarbonate resin composition.

Conventionally, as a method for obtaining a polycarbonate resin, isosorbide (hereinafter, may be abbreviated as ISB), which is a dihydroxy compound obtained from a biomass resource, is used as a monomer component, and a monohydroxy compound produced as a by-product by transesterification with a carbonic acid diester. A method of obtaining a polycarbonate resin while distilling off the mixture under reduced pressure has been proposed (see, for example, Patent Documents 1 to 4). Further, the polycarbonate resin obtained from ISB is being studied for use in an optical film by taking advantage of its excellent optical properties in addition to its use as a molding material utilizing heat resistance (see, for example, Patent Document 5). ..

In a general polarizer protective film, an ultraviolet absorber is added to protect the polarizer from ultraviolet rays. However, a large amount of the ultraviolet absorber is required, and there are problems such as bleed-out. In order to eliminate them, a method of adding an ultraviolet absorber having high compatibility with a resin or a polymer having an ultraviolet absorbing function is known (see, for example, Patent Document 6).

However, the cellulose ester film generally used for the polarizer protective film has a problem that it has high water absorption and its durability is insufficient when it is used for a large-sized television or the like. Further, a polarizer protective film using an acrylic resin has also been proposed (see, for example, Patent Document 7), but it is brittle and may break during handling, making it difficult to make a thin film.

Further, in the case of a display using a general polarizing plate, since the light through the polarizing plate is linearly polarized, when the display is viewed through polarized sunglasses, it may be blacked out depending on the angle. In order to solve this problem, the surface layer of the polarizer protective film may be a retardation film (see, for example, Patent Document 8). These retardation films also contain an ultraviolet absorber in order to protect the polarizer from ultraviolet rays.

For example, when a cycloolefin polymer (hereinafter sometimes abbreviated as COP) is used, in order to prevent bleed-out and roll stains, there is a technique in which two types and three layers are used and only the core layer contains an ultraviolet absorber. (See, for example, Patent Document 9).

International Publication No. 2004/1110106 Japanese Patent Application Laid-Open No. 2006-232897 Japanese Patent Application Laid-Open No. 2006-28441 Japanese Patent Application Laid-Open No. 2008-24919 Japanese Patent Application Laid-Open No. 2011-021171 Japanese Patent Application Laid-Open No. 2002-0473557 Japanese Patent Application Laid-Open No. 2013-83956 Japanese Patent Application Laid-Open No. 2011-137954 Japanese Patent Application Laid-Open No. 2015-31753

However, since the polycarbonate resin obtained from ISB hardly absorbs ultraviolet rays, it is necessary to contain a large amount of ultraviolet absorbers in order to use it in the polarizer protective film. On the other hand, when the polycarbonate resin contains a large amount of ultraviolet absorber, the heat resistance of the film is lowered, the film becomes turbid due to the bleed-out substance, foreign matter on the film due to roll stains, and the appearance of the film such as gear marks are poor. , There is a problem such as a decrease in the uniformity of the film thickness. In addition, roll contamination or the like may occur due to a specific compound.

Therefore, an object of the present invention is to solve these problems, use a specific polycarbonate resin, and contain a specific ultraviolet absorber to reduce the heat resistance of the film, make the film turbid due to bleed-out substances, and stain the roll. It is an object of the present invention to provide a polycarbonate resin film which has a uniform film thickness and absorbs a specific ultraviolet ray without problems such as foreign matter of the film and poor appearance of the film such as gear marks.

As a result of diligent studies to solve the above problems, the present inventors used a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following formula (1), and added a specific ultraviolet absorber. High quality that absorbs specific ultraviolet rays without problems such as deterioration of heat resistance of the film, turbidity of the film due to bleed-out substances, foreign matter of the film due to roll stains, and poor appearance of the film such as gear marks. The present invention has been reached by finding that the film is provided. That is, the gist of the present invention lies in the following [1] to [6].

[1] The melting point is 135 ° C. or higher and lower than 300 ° C. and the weight is reduced by 5% with respect to 100 parts by weight of the polycarbonate resin containing the structural unit derived from the dihydroxy compound represented by the following formula (1) and 100 parts by weight of the polycarbonate resin. A polycarbonate resin film made of a polycarbonate resin composition containing an ultraviolet absorber having a temperature higher than 240 ° C. in an amount of more than 0.45 parts by weight and 7 parts by weight or less, and having a light transmittance of 0.001% or more at a wavelength of 380 nm. A polycarbonate resin film having a thickness of 15 μm or less and a thickness of 5 μm to 120 μm.

[2] The polycarbonate resin film according to [1], wherein the content of the compound represented by the following formula (3) in the polycarbonate resin is 10 ppm by weight or more and 1200 ppm by weight or less.

[3] The polycarbonate resin film according to [1] or [2], wherein the ultraviolet absorber is a triazine-based, benzotriazole-based, quinolinone-based, benzoxazole-based or indole-based.
[4] The polycarbonate resin film according to any one of [1] to [3], wherein the in-plane phase difference at 548 nm is 100 nm or more and 200 nm or less.
[5] A polarizing element protective film using the polycarbonate resin film according to any one of [1] to [4].
[6] The melting point is 135 ° C. or higher and lower than 300 ° C. and the weight is reduced by 5% with respect to 100 parts by weight of the polycarbonate resin containing the structural unit derived from the dihydroxy compound represented by the following formula (1) and 100 parts by weight of the polycarbonate resin. An ultraviolet absorber having a temperature higher than 240 ° C. is contained in an amount of more than 0.45 parts by weight and 7 parts by weight or less, and the content of the compound represented by the following formula (3) in the polycarbonate resin is 10% by weight or more and 1200% by weight. Polycarbonate resin composition of ppm or less.

According to the present invention, even though a large amount of ultraviolet absorber is contained, the heat resistance of the film is lowered when the film is formed, the film becomes turbid due to bleed-out substances, foreign substances on the film due to roll stains, and gears. It is possible to provide an optical film showing high performance as a polarizer protective film without causing problems such as poor appearance of the film such as marks. Further, since roll stains are not generated, defective appearance products in molding can be significantly reduced, so that productivity, workability, and product quality can be improved.

Hereinafter, embodiments of the present invention will be described in detail, but the description of the constituent elements described below is an example (representative example) of the embodiments of the present invention, and the present invention is described below as long as the gist thereof is not exceeded. It is not limited to the contents of.

The polycarbonate resin film of the present invention comprises a polycarbonate resin composition containing a polycarbonate resin and an ultraviolet absorber.

[Polycarbonate resin]
The polycarbonate resin composition in the present invention contains a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following formula (1).

(End group structure of polycarbonate resin)
The polycarbonate resin can be produced by polycondensing a dihydroxy compound, a carbonic acid diester, and a catalyst under melting. As the carbonic acid diester, those described later can be used. Above all, it is preferable to use diphenyl carbonate.

In this case, the total number (B) of the number (A) of the number of terminal groups (hereinafter, may be referred to as "phenyl group terminal") represented by the following structural formula (2) in the produced polycarbonate resin. The ratio (A / B) to the ratio (A / B) is preferably in the range of 75% or more and less than 98%.

Further, the ratio (A / B) of the number of phenyl group terminals (A) to the total number of terminals (B) of the polycarbonate resin is more preferably in the range of 76% or more, and more preferably in the range of 77% or more. Is particularly preferable. Further, it is more preferably in the range of 96% or less, and particularly preferably in the range of 95% or less.

If the ratio (A / B) of the number of phenyl group terminals (A) to the total number of terminals (B) is less than 75%, the molded product has a poor appearance called silver during injection molding, and bubbles in extrusion molding. Is likely to occur. Further, when the ratio (A / B) of the number of phenyl group terminals (A) to the total number of terminals (B) is more than 98%, the appearance defect in injection molding or extrusion molding tends to decrease. Further, if an attempt is made to obtain a polycarbonate resin having an (A / B) content of more than 98%, the polymerization conditions may be severe, a long-term reaction may be required, and as a result, the polycarbonate resin may deteriorate, resulting in poor color tone. It is very likely that you will only get things.

The method for adjusting the ratio (A / B) of the number of phenyl group terminals (A) to the total number of terminals (B) in the polycarbonate resin to the above range is not particularly limited. For example, the ratio of the amount of carbonic acid diester to the total dihydroxy compound used in the reaction can be adjusted within a range in which a desired high molecular weight compound can be obtained, the residual monomer can be removed from the reaction system by degassing in the subsequent stage of the polymerization reaction, or the latter stage of the polymerization reaction. The ratio (A / B) of the number of phenyl group terminals (A) to the total number of terminals (B) is adjusted to the above range by increasing the reaction rate by increasing the stirring efficiency of the reactor in can do.

The ratio of phenyl group terminals in the polycarbonate resin can be calculated by ¹ H-NMR spectrum measurement using deuterated chloroform to which TMS (tetramethylsilane) is added as a measurement solvent with an NMR spectrometer.
The proportions of the dihydroxy compound having the bonding structure of the structural formula (1), the alicyclic dihydroxy compound, and other dihydroxy compounds used as needed are the proportions of the polycarbonate resin used in the present invention. It is appropriately adjusted according to the proportion of the constituent units derived from the dihydroxy compound.

(Content of compound represented by formula (3) and content control method)
The polycarbonate resin in the present invention more preferably contains a specific amount of a special oligomer component represented by the following formula (3).

If the amount of the above compound is too small, excessive heat may be applied or the reaction residence time may be lengthened in the production stage of the polycarbonate resin, which may cause deterioration of the color tone of the polymer. Further, if the amount is too large, there is a problem that the device is contaminated at the time of molding, or a poor appearance of the molded product is caused. Therefore, the content of the compound represented by the formula (3) in the polycarbonate resin in the present invention is preferably 10% by weight or more and 1200% by weight or less.

The content of the compound represented by the formula (3) in the polycarbonate resin of the present invention is more preferably 15 ppm by weight or more, and particularly preferably 20 ppm by weight or more. Further, it is more preferably 650 ppm by weight or less, and particularly preferably 400 ppm by weight or less. When the content of the compound represented by the formula (3) in the polycarbonate resin is within the above range, there is no stain or odor during molding, and the molding appearance is good, which is preferable.

In order to adjust the content of the compound represented by the formula (3), the ratio (A / B) of the number of phenyl group terminals (A) to the total number of terminals (B) is 98 during the production of the polycarbonate resin. % Or less is preferable.

Further, by setting the pressure in the final polymerization tank to 1 kPa or less and the polymerization time at a temperature higher than 220 ° C. to less than 2 hours, the generation of the compound represented by the formula (3) can be suppressed. In particular, by making the final polymerization tank a horizontal reaction tank, it is possible to dramatically improve the devolatilization efficiency. Further, the compound represented by the formula (3) can be controlled to a specific amount by devolatile from the vacuum vent with an extruder or by injecting water at the time of devolatile.

The polycarbonate resin in the present invention is usually obtained by polycondensing a dihydroxy compound, a carbonic acid diester, and a catalyst under melting, as described later. In this polycondensation reaction, a monohydroxy compound is produced as a desorbing component from the carbonic acid diester.

For example, when diphenyl carbonate is used as the carbonic acid diester, the monohydroxy compound produced is phenol. At this time, if the content of the monohydroxy compound in the obtained polycarbonate resin is large, problems of contamination of the apparatus during molding and odor may occur.

The upper limit of the content of the monohydroxy compound in the polycarbonate resin in the present invention is not particularly limited, but is usually 1200 ppm by weight or less, preferably 650 ppm by weight or less, and particularly 500 ppm by weight or less. Is preferable. At the time of producing the polycarbonate resin, the content of the monohydroxy compound in the polycarbonate resin is reduced by using an appropriate amount of a specific phosphorus-based compound as a catalyst deactivating agent as described later and further performing a sufficient devolatile treatment. Moreover, the occurrence under heating can be suppressed. Details of the method for measuring the amount of the monohydroxy compound in the polycarbonate resin will be described in the section of Examples.

The lower limit is not particularly limited, but is usually 0.1 wt ppm or more, preferably 1 wt ppm or more, and particularly preferably 10 wt ppm or more. If these amounts are too small, it is necessary to apply excessive heat or prolong the reaction residence time in the purification step, which may cause deterioration of the color tone of the polymer, and the above range is preferable.

[Manufacturing method of polycarbonate resin]
Hereinafter, the method for producing the polycarbonate resin in the present invention will be described in detail.
<Raw materials>
(Dihydroxy compound)
The polycarbonate resin in the present invention is a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following formula (1).

In the present invention, in addition to the structural unit derived from the dihydroxy compound represented by the above formula (1), the polycarbonate resin is, if necessary, a dihydroxy compound represented by the following formula (4) and the following formula (5). One or more selected from the group consisting of a dihydroxy compound represented by the following formula (6), a dihydroxy compound represented by the following formula (7), and a dihydroxy compound represented by the following formula (8). It preferably contains structural units derived from dihydroxy compounds.

HO-R ^5- OH (5)
(In the above formula (5), R ⁵ represents a substituted or unsubstituted cycloalkylene group having 4 to 20 carbon atoms.)
_{^{HO-CH 2 -R 6 -CH 2}} -OH (6)
(In the above formula (6), R ⁶ represents a substituted or unsubstituted cycloalkylene group having 4 to 20 carbon atoms.)
H- (OR ⁷ ) _p- OH (7)
(In the above formula (7), R ⁷ represents a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms, and p is an integer of 2 to 100.)
HO-R ^8- OH (8)
(In the above formula (8), R ⁸ represents a substituted or unsubstituted alkylene group having 2 to 20 carbon atoms.)
In the following, the carbon number of each group means the total carbon number including the carbon number of the substituent when the group has a substituent.

(Dihydroxy compound represented by the formula (1))
The polycarbonate resin in the present invention contains a structural unit derived from the dihydroxy compound represented by the above formula (1).

Examples of the dihydroxy compound represented by the above formula (1) include anhydrous sugar alcohols such as isosorbide, isomannide, and isoidet having a stereoisomeric relationship. One of these may be used alone, or two or more thereof may be used in combination. Among these dihydroxy compounds, isosorbide obtained by dehydration condensation of sorbitol produced from various readily available starches, which is abundant as a resource, is easy to obtain and produce, optical properties, and moldability. Most preferable from the viewpoint of.

When the polycarbonate resin simultaneously contains a structural unit other than the structural unit derived from the dihydroxy compound represented by the above formula (1), the ratio is not particularly limited and may be appropriately set according to the required performance of the polycarbonate resin. Good.

(Dihydroxy compounds represented by formulas (4) to (8))
In the present invention, the polycarbonate resin is, if necessary, a dihydroxy compound represented by the above formula (4), a dihydroxy compound represented by the above formula (5), a dihydroxy compound represented by the above formula (6), and the above. It can contain a structural unit derived from one or more dihydroxy compounds selected from the group consisting of the dihydroxy compound represented by the formula (7) and the dihydroxy compound represented by the above formula (8).

[Dihydroxy compound represented by the formula (4)]
The dihydroxy compound represented by the above formula (4) has a cyclic ether structure in the molecule and is a compound called spiroglycol.

[Dihydroxy compound represented by the formula (5)]
Dihydroxy compound represented by formula (5) is 4 to 20 carbon atoms in R ^5, is preferably an alicyclic dihydroxy compound with a substituted or unsubstituted cycloalkylene group having 4 to 18 carbon atoms. Here, when R ⁵ has a substituent, examples of the substituent include a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms. When the alkyl group has a substituent, examples of the substituent include an alkoxy group such as a methoxy group, an ethoxy group and a propoxy group, and an aryl group such as a phenyl group and a naphthyl group.

Since this dihydroxy compound has a ring structure, it is possible to increase the toughness of the molded product when the obtained polycarbonate resin is molded, and in particular, the toughness when molded into a film can be enhanced.

The cycloalkylene group of R ⁵ is not particularly limited as long as it is a hydrocarbon group having a ring structure, and may have a bridging structure having a bridgehead carbon atom. From the standpoint of being able to reduce the easy and the amount of impurities the preparation of dihydroxy compound, the dihydroxy compound represented by the formula (5) is a compound containing a 5-membered ring structure or 6-membered ring structure, i.e., is R ⁵ A dihydroxy compound which is a substituted or unsubstituted cyclopentylene group or a substituted or unsubstituted cyclohexylene group is preferable. With such a dihydroxy compound, the heat resistance of the obtained polycarbonate resin can be increased by including a 5-membered ring structure or a 6-membered ring structure. The 6-membered ring structure may be fixed in a chair shape or a boat shape by a covalent bond.

Among them, the dihydroxy compound represented by the formula (5) is preferably R ⁵ is various isomers represented by the following formula (9). Here, in the formula (9), R ¹¹ represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms. When R ¹¹ is an alkyl group having 1 to 12 carbon atoms having a substituent, examples of the substituent include an alkoxy group such as a methoxy group, an ethoxy group and a propoxy group, and an aryl group such as a phenyl group and a naphthyl group. Be done.

More specifically, as the dihydroxy compound represented by the above formula (5), tetramethylcyclobutanediol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, 1,2-cyclopentanediol, 1,3-Cyclopentanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 2-methyl-1,4-cyclohexanediol, tricyclodecanediols, pentacyclodiols Etc., but are not limited to these.
These may be used alone or in combination of two or more.

[Dihydroxy compound represented by the formula (6)]
Dihydroxy compound represented by formula (6) is 4 to 20 carbon atoms in R ^6, preferably the alicyclic dihydroxy compound with a substituted or unsubstituted cycloalkylene group having 3 to 18 carbon atoms. Here, when R ⁶ has a substituent, examples of the substituent include a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms. When the alkyl group has a substituent, examples of the substituent include an alkoxy group such as a methoxy group, an ethoxy group and a propoxy group, and an aryl group such as a phenyl group and a naphthyl group.

Since this dihydroxy compound has a ring structure, it is possible to increase the toughness of the molded product when the obtained polycarbonate resin is molded, and in particular, the toughness when molded into a film can be enhanced.

The cycloalkylene group of R ⁶ is not particularly limited as long as it is a hydrocarbon group having a ring structure, and may have a crosslinked structure having a bridgehead carbon atom. From the standpoint of being able to reduce the easy and the amount of impurities the preparation of dihydroxy compound, the dihydroxy compound represented by the above formula (6) is a compound containing a 5-membered ring structure or 6-membered ring structure, i.e., R ⁶ is A dihydroxy compound which is a substituted or unsubstituted cyclopentylene group or a substituted or unsubstituted cyclohexylene group is preferable.

With such a dihydroxy compound, the heat resistance of the obtained polycarbonate resin can be increased by including a 5-membered ring structure or a 6-membered ring structure. The 6-membered ring structure may be fixed in a chair shape or a boat shape by a covalent bond. Among the dihydroxy compounds represented by the above formula (6), it is preferable that R ⁶ is various isomers represented by the above formula (9).

More specifically, the dihydroxy compound represented by the above formula (6) includes 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, and 3,8-bis (hydroxy). methyl) tricyclo [5.2.1.0 ^2.6] decane, 3,9-bis (hydroxymethyl) tricyclo [5.2.1.0 ^2.6] decane, 4,8-bis (hydroxymethyl) tricyclo [5.2.1.0 ^2.6] decane, 4,9-bis (hydroxymethyl) tricyclo [5.2.1.0 ^2.6] Although decane and the like, as being limited to these It's not a thing.

One of these may be used alone, or two or more thereof may be used in combination. That is, these dihydroxy compounds may be obtained as a mixture of isomers for manufacturing reasons, but in that case, they can also be used as they are as a mixture of isomers.

For example, 3,8-bis (hydroxymethyl) tricyclo [5.2.1.0 ^2.6] decane, 3,9-bis (hydroxymethyl) tricyclo [5.2.1.0 ^2.6] decane, 4,8-bis (hydroxymethyl) tricyclo [5.2.1.0 ^2.6] decane, and 4,9-bis (hydroxymethyl) tricyclo [5.2.1.0 ^2.6] decane A mixture can be used.

Among the specific examples of the dihydroxy compound represented by the above formula (6), cyclohexanedimethanol is particularly preferable, and 1,4-cyclohexanedimethanol, 1 from the viewpoint of easy availability and handling. , 3-Cyclohexanedimethanol, 1,2-Cyclohexanedimethanol are preferred.

[Dihydroxy compound represented by the formula (7)]
The dihydroxy compound represented by the above formula (7) is a compound having a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms, preferably 2 to 5 carbon atoms in R ⁷ . p is an integer of 2 to 100, preferably an integer of 6 to 50, and more preferably an integer of 12 to 40.

Specific examples of the dihydroxy compound represented by the above formula (7) include, but are not limited to, diethylene glycol, triethylene glycol, polyethylene glycol (molecular weight 150 to 4000) and the like. As the dihydroxy compound represented by the above formula (7), polyethylene glycol having a molecular weight of 300 to 2000 is preferable, and polyethylene glycol having a molecular weight of 600 to 1500 is particularly preferable.
These may be used alone or in combination of two or more.

[Dihydroxy compound represented by the formula (8)]
Dihydroxy compound represented by formula (8) is 2 to 20 carbon atoms in R ^8, preferably a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms. When the alkylene group of R ⁸ has a substituent, the substituent includes an alkyl group having 1 to 5 carbon atoms.

Among the dihydroxy compounds represented by the above formula (8), the dihydroxy compounds in which R ⁸ is a substituted or unsubstituted alkylene group having 2 to 20 carbon atoms are specifically ethylene glycol, propylene glycol, 1,4. -Butandiol, 1,6-hexanediol and the like can be mentioned, but the present invention is not limited thereto.

Among these dihydroxy compounds, 1,3-propanediol and 1,6-propanediol and 1,6-propanediol are considered to be easily available, easy to handle, highly reactive during polymerization, and the hue of the obtained polycarbonate resin. Hexanediol is preferred. From the viewpoint of heat resistance, spiroglycol having an acetal ring is preferable. These may be used alone or in combination of two or more depending on the required performance of the obtained polycarbonate resin.

In the present invention, the polycarbonate resin has a structural unit derived from the dihydroxy compound represented by the above formula (4), a structural unit derived from the dihydroxy compound represented by the above formula (5), and the above formula (6). Among the structural units derived from the dihydroxy compound represented, the structural units derived from the dihydroxy compound represented by the above formula (7), and the structural units derived from the dihydroxy compound represented by the above formula (8), the above formula ( It preferably contains a structural unit derived from the dihydroxy compound represented by 6) and / or a structural unit derived from the dihydroxy compound represented by the above formula (7). Further, it is more preferable to contain a structural unit derived from the dihydroxy compound represented by the above formula (6) because of its reactivity, heat resistance, and less decomposition due to heat retention.

(Other dihydroxy compounds)
In the present invention, the polycarbonate resin may replace the structural unit derived from the dihydroxy compound represented by the above formulas (4) to (8) with a structural unit derived from another dihydroxy compound, if necessary.
Examples of other dihydroxy compounds include bisphenols, ethylene oxide (EO) additions of bisphenols, fluorene compounds and the like.

<Bisphenols>
Examples of bisphenols include 2,2-bis (4-hydroxyphenyl) propane (= bisphenol A), 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, and 2,2-bis ( 4-Hydroxy-3,5-diethylphenyl) propane, 2,2-bis (4-hydroxy- (3,5-diphenyl) phenyl) propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) ) Propane, 2,2-bis (4-hydroxyphenyl) pentane, 2,4'-dihydroxy-diphenylmethane, bis (4-hydroxyphenyl) methane, bis (4-hydroxy-5-nitrophenyl) methane, 1,1 -Bis (4-hydroxyphenyl) ethane, 3,3-bis (4-hydroxyphenyl) pentane, 1,1-bis (4-hydroxyphenyl) cyclohexane, bis (4-hydroxyphenyl) sulfone, 2,4'- Dihydroxydiphenylsulfone, bis (4-hydroxyphenyl) sulfide, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dichlorodiphenyl ether, 4,4'-dihydroxy-2,5-diethoxydiphenyl ether And so on.

<Ethylene oxide (EO) additions of bisphenols>
Examples of the ethylene oxide (EO) additions of bisphenols include those in which ethylene oxide (EO) is added to the above-mentioned bisphenol compounds.

<Fluorene compound>
Examples of the fluorene compound include 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, and 9,9-bis (4-hydroxy-3-ethyl). Phenyl) fluorene, 9,9-bis (4-hydroxy-3-n-propylphenyl) fluorene, 9,9-bis (4-hydroxy-3-isopropylphenyl) fluorene, 9,9-bis (4-hydroxy-) 3-n-butylphenyl) fluorene, 9,9-bis (4-hydroxy-3-sec-butylphenyl) fluorene, 9,9-bis (4-hydroxy-3-tert-propylphenyl) fluorene, 9,9 -Bis (4-hydroxy-3-cyclohexylphenyl) fluorene, 9,9-bis (4-hydroxy-3-phenylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene, 9 , 9-bis (4- (2-hydroxyethoxy) -3-methylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-isopropylphenyl) fluorene, 9,9-bis (4) -(2-Hydroxyethoxy) -3-isobutylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-tert-butylphenyl) fluorene, 9,9-bis (4- (2-) Hydroxyethoxy) -3-cyclohexylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-phenylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3, 5-Dimethylphenyl) Fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-tert-butyl-6-methylphenyl) fluorene, 9,9-bis (4- (3-hydroxy-2,,) 2-Dimethylpropoxy) phenyl) fluorene and the like can be mentioned.

These may be used alone or in combination of two or more. However, since dihydroxy compounds having an aromatic ring in the structure other than those represented by the above formula (1) may adversely affect the optical properties, the structural unit derived from such a dihydroxy compound is polycarbonate. It is preferably used in an amount of 50 mol% or less, more preferably 20 mol% or less, and further preferably 5 mol% or less, based on the total structural units derived from the dihydroxy compound in the resin. In particular, the polycarbonate resin preferably does not contain structural units derived from dihydroxy compounds having an aromatic ring in the structure other than those represented by the above formula (1).

[Content ratio of structural units derived from dihydroxy compounds]
In the present invention, the content ratio of the structural unit derived from the dihydroxy compound represented by the above formula (1) contained in the polycarbonate resin is preferably 20% by weight or more with respect to the total of the structural units derived from the dihydroxy compound. It is more preferably 25% by weight or more, still more preferably 30% by weight or more. Further, it is usually 95% by weight or less, preferably 90% by weight or less.

If the content ratio of the structural unit is excessively small, the heat resistance may be low and the surface hardness may be inferior. Further, if the content ratio of the structural unit is excessively large, the glass transition temperature of the polycarbonate resin may become excessively high, making molding difficult or the water absorption rate may deteriorate.

Further, the polycarbonate resin is represented by the dihydroxy compound represented by the above formula (4), the dihydroxy compound represented by the above formula (5), the dihydroxy compound represented by the above formula (6), and the above formula (7). When a structural unit derived from one or more dihydroxy compounds selected from the group consisting of the dihydroxy compound and the dihydroxy compound represented by the above formula (8) is contained, the content ratio is derived from the dihydroxy compound contained in the polycarbonate resin. 0.1% by weight or more and less than 20% by weight, more preferably 0.1% by weight or more and 18% by weight or less, still more preferably 0.2% by weight or more and 15% by weight or less, based on the total of the structural units. Appropriate.

By including the structural unit derived from the dihydroxy compound represented by the above formulas (4) to (8) in the polycarbonate resin at the above lower limit value or more, foreign substances and bubbles due to heat are generated when the polycarbonate resin is melted and molded. Can be prevented from occurring, and coloring of the polycarbonate resin can be prevented. However, if the number of structural units is excessively large, the light resistance tends to decrease when a molded product is formed.

All dihydroxy compounds used in the production of the polycarbonate resin in the present invention include stabilizers such as reducing agents, antioxidants, oxygen scavengers, light stabilizers, antacids, pH stabilizers or heat stabilizers. You may. In particular, since the specific dihydroxy compound in the present invention is easily altered under acidic conditions, it is preferable to contain a basic stabilizer.

Examples of the basic stabilizer include hydroxides, carbonates, phosphates, phosphites, and hypophates of Group 1 or Group 2 metals in the long-period periodic table (Nomenclature of Inorganic Chemistry IUPAC Recommissions 2005). Phosphates, boroates and fatty acid salts, tetramethylammonium hydroxides, tetraethylammonium hydroxides, tetrapropylammonium hydroxides, tetrabutylammonium hydroxides, trimethylethylammonium hydroxides, trimethylbenzylammonium hydroxides, trimethylphenylammonium hydroxides , Triethylmethylammonium hydroxide, triethylbenzylammonium hydroxide, triethylphenylammonium hydroxide, tributylbenzylammonium hydroxide, tributylphenylammonium hydroxide, tetraphenylammonium hydroxide, benzyltriphenylammonium hydroxide, methyltriphenylammonium hydroxide And basic ammonium compounds such as butyltriphenylammonium hydroxide, diethylamine, dibutylamine, triethylamine, morpholine, N-methylmorpholine, pyrrolidine, piperidine, 3-amino-1-propanol, ethylenediamine, N-methyldiethanolamine, diethylethanolamine , 4-Aminopyridine, 2-Aminopyridine, N, N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 2-Hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 2-Dimethylaminoimidazole, 2- Amine compounds such as methoxyimidazole, imidazole, 2-mercaptoimidazole, 2-methylimidazole and aminoquinolin, and hindered amine compounds such as di- (tert-butyl) amine and 2,2,6,6-tetramethylpiperidine Can be mentioned. Among these stabilizers, tetramethylammonium hydroxide, imidazole or hindered amine compounds are preferable from the viewpoint of stabilizing effect.

The content of these basic stabilizers in all the dihydroxy compounds used in the present invention is not particularly limited, but since the specific dihydroxy compounds used in the present invention are unstable in an acidic state, the above stabilizers are used. It is preferable to add a stabilizer so that the pH of the aqueous solution of the specific dihydroxy compound contained is around 7.

If the amount of the basic stabilizer is too small, the effect of preventing the alteration of the specific dihydroxy compound may not be obtained, and if it is too large, the specific dihydroxy compound may be denatured. Therefore, the basic stabilizer is preferably 0.0001% by weight to 1% by weight, more preferably 0.001% by weight to 0.1% by weight, based on each of the dihydroxy compounds used in the present invention. is there.

When these basic stabilizers are used as a raw material for producing a polycarbonate resin while being contained in the dihydroxy compound used in the present invention, the basic stabilizer itself becomes a polymerization catalyst, which not only makes it difficult to control the polymerization rate or quality, but also makes it difficult to control the polymerization rate or quality. It causes deterioration of the resin hue.

Therefore, for a specific dihydroxy compound or the other dihydroxy compound containing a basic stabilizer, the basic stabilizer is removed by an ion exchange resin, distillation, or the like before being used as a raw material for producing a polycarbonate resin. Is preferable.

In addition, since the specific dihydroxy compound used in the present invention is easily oxidized by oxygen, it should be prevented from being mixed with water during storage or handling during production to prevent decomposition by oxygen, and should be removed. It is preferable to use an oxygen agent or to create a nitrogen atmosphere.

(Carbonate diester)
The polycarbonate resin in the present invention can be obtained by polycondensing a dihydroxy compound containing the above-mentioned specific dihydroxy compound and a carbonic acid diester as raw materials by a transesterification reaction. As the carbonic acid diester used, those represented by the following formula (10) are usually mentioned. One of these carbonic acid diesters may be used alone, or two or more thereof may be mixed and used.

In the above formula (10), A ¹ and A ² are an aliphatic hydrocarbon group having 1 to 18 carbon atoms substituted or unsubstituted, or an aromatic hydrocarbon group substituted or unsubstituted, respectively, and A ¹ and A are A. It may be the same as or different from ² . Preferred A ¹ and A ² are substituted or unsubstituted aromatic hydrocarbon groups, and more preferred are unsubstituted aromatic hydrocarbon groups.

Examples of the carbonic acid diester represented by the above formula (10) include substituted diphenyl carbonates such as diphenyl carbonate (DPC) and ditril carbonate, dimethyl carbonate, diethyl carbonate, di-t-butyl carbonate and the like. Of these, diphenyl carbonate or substituted diphenyl carbonate is preferable, and diphenyl carbonate is particularly preferable.

The carbonic acid diester may contain impurities such as chloride ions, and the impurities may inhibit the polymerization reaction or deteriorate the hue of the obtained polycarbonate resin. Therefore, if necessary, distillation or the like may be used. It is preferable to use the one purified by.

<Transesterification reaction catalyst>
The polycarbonate resin in the present invention is produced by transesterifying the above-mentioned dihydroxy compound with a carbonic acid diester. More specifically, it is obtained by transesterifying and removing by-produced monohydroxy compounds and the like from the system.

In the transesterification reaction, polycondensation is performed in the presence of a transesterification reaction catalyst, but the transesterification reaction catalyst (hereinafter, simply referred to as a catalyst or a polymerization catalyst) that can be used in the production of the polycarbonate resin in the present invention may be used. ) Can have a very large effect on the reaction rate or the quality of the polycarbonate resin obtained by transesterification.

The catalyst used is not limited as long as it can satisfy the transparency, hue, heat resistance, weather resistance, and mechanical strength of the produced polycarbonate resin. For example, metal compounds of Group 1 or Group 2 (hereinafter, simply referred to as "Group 1" and "Group 2") in the long periodic table, as well as basic boron compounds, basic phosphorus compounds, and basic ammonium compounds. And basic compounds such as amine compounds. Preferably, Group 1 metal compounds and / or Group 2 metal compounds are used.

Examples of the Group 1 metal compound include sodium hydroxide, potassium hydroxide, lithium hydroxide, cesium hydroxide, sodium hydrogen carbonate, potassium hydrogen carbonate, lithium hydrogen carbonate, cesium hydrogen carbonate, sodium carbonate, potassium carbonate, and carbon dioxide. Lithium, cesium carbonate, sodium acetate, potassium acetate, lithium acetate, cesium acetate, sodium stearate, potassium stearate, lithium stearate, cesium stearate, sodium boron hydride, potassium borohydride, lithium boron hydride, hydrogenation Cesium boron, sodium boron phenylated, potassium boron phenylated, lithium boron phenylated, cesium phenylated boron, sodium benzoate, potassium benzoate, lithium benzoate, cesium benzoate, disodium hydrogen phosphate, dipotassium hydrogen phosphate , 2 lithium hydrogen phosphate, 2 cesium hydrogen phosphate, 2 sodium phenyl phosphate, 2 potassium phenyl phosphate, 2 lithium phenyl phosphate, 2 cesium phenyl phosphate, sodium, potassium, lithium, cesium alcolate, phenolate , 2 sodium salt, 2 potassium salt, 2 lithium salt, 2 cesium salt and the like of bisphenol A. Of these, a lithium compound is preferable from the viewpoint of polymerization activity and the hue of the obtained polycarbonate resin.

Examples of the Group 2 metal compound include calcium hydroxide, barium hydroxide, magnesium hydroxide, strontium hydroxide, calcium hydrogen carbonate, barium hydrogen carbonate, magnesium hydrogen carbonate, strontium hydrogen carbonate, calcium carbonate, barium carbonate, and carbon dioxide. Examples thereof include magnesium, strontium carbonate, calcium acetate, barium acetate, magnesium acetate, strontium acetate, calcium stearate, barium stearate, magnesium stearate and strontium stearate.

Of these, magnesium compounds, calcium compounds or barium compounds are preferable, and magnesium compounds and / or calcium compounds are more preferable, and calcium compounds are most preferable, from the viewpoint of polymerization activity and the hue of the obtained polycarbonate resin.

It is also possible to use a basic compound such as a basic boron compound, a basic phosphorus compound, a basic ammonium compound, and an amine compound in combination with the above-mentioned Group 1 metal compound and / or Group 2 metal compound. However, it is particularly preferable to use only Group 1 metal compounds and / or Group 2 metal compounds.

Examples of the basic boron compound include tetramethylboron, tetraethylboron, tetrapropylboron, tetrabutylboron, trimethylethylboron, trimethylbenzylboron, trimethylphenylboron, triethylmethylboron, triethylbenzylboron, and triethylphenylboron. Sodium salts such as tributylbenzylboron, tributylphenylboron, tetraphenylboron, benzyltriphenylboron, methyltriphenylboron, butyltriphenylboron, potassium salt, lithium salt, calcium salt, barium salt, magnesium salt, strontium salt, etc. Can be mentioned.

Examples of the basic phosphorus compound include triethylphosphine, tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine, triphenylphosphine, tributylphosphine and quaternary phosphonium salts.

Examples of the basic ammonium compound include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylethylammonium hydroxide, trimethylbenzylammonium hydroxide, and trimethylphenylammonium hydroxide. Do, triethylmethylammonium hydroxide, triethylbenzylammonium hydroxide, triethylphenylammonium hydroxide, tributylbenzylammonium hydroxide, tributylphenylammonium hydroxide, tetraphenylammonium hydroxide, benzyltriphenylammonium hydroxide, methyltriphenylammonium hydroxide Do and butyltriphenylammonium hydroxide and the like.

Examples of the amine-based compound include 4-aminopyridine, 2-aminopyridine, N, N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 2-hydroxypyridine, 2-methoxypyridine, and 4-methoxypyridine. , 2-Dimethylaminoimidazole, 2-methoxyimidazole, imidazole, 2-mercaptoimidazole, 2-methylimidazole, aminoquinoline, guanidine and the like.

The amount of the polymerization catalyst used is preferably 0.1 μmol to 300 μmol, more preferably 0.5 μmol to 100 μmol, and particularly preferably 1 μmol to 50 μmol per 1 mol of the total dihydroxy compound used for the polymerization.

Among them, when a compound containing at least one metal selected from the group consisting of Group 2 and lithium in the long periodic table is used, particularly when a magnesium compound and / or a calcium compound is used, the total dihydroxy compound is used as the amount of metal. It is preferably 0.1 μmol or more, more preferably 0.3 μmol or more, and particularly preferably 0.5 μmol or more per 1 mol. The upper limit is preferably 20 μmol or less, more preferably 10 μmol or less, still more preferably 5 μmol or less, and particularly preferably 3 μmol or less.

If the amount of the catalyst is too small, the polymerization rate becomes slow, so that the polymerization temperature must be raised by that amount in order to obtain a polycarbonate resin having a desired molecular weight. Therefore, there is a high possibility that the hue of the obtained polycarbonate resin will deteriorate, and the unreacted raw material will volatilize during the polymerization to disrupt the molar ratio of the dihydroxy compound and the carbonic acid diester, and the desired molecular weight may not be reached. There is sex. On the other hand, if the amount of the polymerization catalyst used is too large, unfavorable side reactions may occur, resulting in deterioration of the hue of the obtained polycarbonate resin or coloring of the resin during molding.

However, among the Group 1 metals, sodium, potassium or cesium may adversely affect the hue if they are contained in a large amount in the polycarbonate resin. Then, these metals may be mixed not only from the catalyst used but also from the raw material or the reactor. Regardless of the source, the total amount of these metal compounds in the polycarbonate resin is preferably 1 wt ppm or less, more preferably 0.5 wt ppm or less as the metal amount.

<Manufacturing method of polycarbonate resin>
The polycarbonate resin in the present invention is obtained by polycondensing a dihydroxy compound containing a specific dihydroxy compound and a carbonic acid diester by a transesterification reaction.

It is preferable that the raw material dihydroxy compound and the carbonic acid diester are uniformly mixed before the transesterification reaction. The mixing temperature is usually 80 ° C. or higher, preferably 90 ° C. or higher. The upper limit thereof is usually 250 ° C. or lower, preferably 200 ° C. or lower, and more preferably 150 ° C. or lower. Above all, 100 ° C. or higher and 120 ° C. or lower is preferable.

If the mixing temperature is too low, the dissolution rate may be slow or the solubility may be insufficient, which often leads to problems such as solidification, and if the mixing temperature is too high, thermal deterioration of the dihydroxy compound may occur. It may adversely affect the hue and thermal stability of the resulting polycarbonate resin.

The operation of mixing the dihydroxy compound containing a specific dihydroxy compound, which is the raw material of the polycarbonate resin in the present invention, with the carbonic acid diester is preferably an oxygen concentration of 10 vol% or less, more preferably 0.0001 vol% to 10 vol%, still more preferably. It is carried out in an atmosphere of 0.0001 vol% to 5 vol%, particularly preferably 0.0001 vol% to 1 vol%. Within the above range, it is possible to prevent deterioration of hue.

In order to obtain the polycarbonate resin in the present invention, it is preferable to use a carbonic acid diester in a molar ratio of 0.94 to 1.04 with respect to all the dihydroxy compounds including the specific dihydroxy compound used in the reaction, and more preferably 0. The molar ratio is 98 to 1.02, more preferably 1.00 to 1.01. When this molar ratio becomes small, the terminal phenyl groups of the produced polycarbonate resin are reduced, and poor appearance during molding is likely to occur.

Further, when this molar ratio becomes large, the rate of the transesterification reaction may decrease, or it may become difficult to produce a polycarbonate resin having a desired molecular weight. The decrease in the transesterification reaction rate may increase the thermal history during the polymerization reaction and deteriorate the hue and weather resistance of the resulting polycarbonate resin.

Furthermore, when the molar ratio of carbonic acid diester to the total dihydroxy compound including the specific dihydroxy compound increases, the amount of residual carbonic acid diester in the obtained polycarbonate resin and the compound represented by the above formula (3) increase, resulting in molding. It may cause problems such as dirt, odor, and poor appearance.

In the present invention, the method of polycondensing a dihydroxy compound and a carbonic acid diester is usually carried out in a multi-step manner using a plurality of reactors in the presence of the above-mentioned catalyst. The reaction type may be a batch type, a continuous type, or a combination of a batch type and a continuous type, but a continuous type in which a polycarbonate resin can be obtained with a smaller thermal history and excellent productivity is preferable.

In the initial stage of polymerization, it is preferable to obtain a prepolymer at a relatively low temperature and low vacuum, and in the late stage of polymerization, it is preferable to raise the molecular weight to a predetermined value at a relatively high temperature and high vacuum. In addition, it is important to appropriately select the jacket temperature and internal temperature at each molecular weight stage and the pressure in the reaction system from the viewpoint of controlling the polymerization rate and the quality of the obtained polycarbonate resin.

For example, if either the temperature or the pressure is changed too quickly before the polymerization reaction reaches a predetermined value, unreacted monomers are distilled out, the molar ratio of the dihydroxy compound and the carbonic acid diester is disturbed, and the polymerization rate is lowered. As a result, the object of the present invention may not be achieved due to the fact that a polymer having a predetermined molecular weight or terminal group cannot be obtained.

Furthermore, it is effective to use a reflux condenser as the polymerization reactor in order to suppress the amount of the monomer distilled, and the effect is particularly large in the reactor at the initial stage of polymerization in which there are many unreacted monomer components. The temperature of the refrigerant introduced into the reflux condenser can be appropriately selected depending on the monomer used, but usually the temperature of the refrigerant introduced into the reflux condenser is 45 to 180 ° C. at the inlet of the reflux condenser. Yes, preferably 80-150 ° C, particularly preferably 100-130 ° C.

If the temperature of the refrigerant is too high, the amount of recirculation is reduced and the effect is reduced. On the contrary, if the temperature of the refrigerant is too low, the distillation efficiency of the monohydroxy compound that should be distilled off tends to decrease. As the refrigerant, hot water, steam, heat medium oil and the like are used, and steam and heat medium oil are preferable.

It is important to select the type and amount of the catalyst described above in order to maintain the polymerization rate appropriately, suppress the distillation of the monomer, and not impair the hue of the final polycarbonate resin. The polycarbonate resin in the present invention is preferably produced by polymerizing in multiple stages using a plurality of reactors using a catalyst.

The reason why the polymerization is carried out in a plurality of reactors is that since a large amount of monomers are contained in the reaction solution at the initial stage of the polymerization reaction, it is important to suppress the volatilization of the monomers while maintaining the required polymerization rate. This is because, in the latter stage of the polymerization reaction, it is important to sufficiently distill off the by-produced monohydroxy compound in order to shift the equilibrium to the polymerization side. As described above, in order to set different polymerization reaction conditions, it is preferable to use a plurality of polymerization reactors arranged in series from the viewpoint of production efficiency.

As described above, the number of reactors used in the production of the polycarbonate resin in the present invention may be at least two or more. From the viewpoint of production efficiency and the like, it is preferably 3 or more, more preferably 3 to 5, and particularly preferably 4. In the present invention, if there are two or more reactors, a plurality of reaction stages having different conditions may be provided in the reactor, or the temperature and pressure may be continuously changed.

In the present invention, the polymerization catalyst can be added to the raw material preparation tank and the raw material storage tank, or can be added directly to the polymerization tank. From the viewpoint of supply stability and polymerization control, a catalyst supply line is installed in the middle of the raw material line before being supplied to the polymerization tank, and the catalyst supply line is preferably supplied as an aqueous solution.

If the temperature of the polymerization reaction is too low, it causes a decrease in productivity and an increase in the thermal history of the product, and if it is too high, it not only causes the monomer to volatilize, but also may promote the decomposition and coloring of the polycarbonate resin. Specifically, in the first-stage reaction, the internal temperature of the polymerization reactor is 130 to 210 ° C, preferably 150 to 205 ° C, and more preferably 170 to 200 ° C.

The pressure (absolute pressure) of the reaction system is 1 to 110 kPa, preferably 5 to 70 kPa, more preferably 7 to 30 kPa (absolute pressure), and the reaction time is 0.1 to 10 hours, preferably 0. It is carried out for 5 to 3 hours while distilling the generated monohydroxy compound out of the reaction system.

From the second stage onward, the pressure of the reaction system is gradually lowered from the pressure of the first stage, and the continuously generated monohydroxy compound is removed from the reaction system. In particular, in order to control the amount of the compound represented by the above formula (3), the internal temperature is set to 15 kPa or less in the second and subsequent stages, and finally the pressure (absolute pressure) of the reaction system is set to 600 Pa or less. The maximum temperature is 190 to 240 ° C., preferably 195 to 235 ° C., usually 0.1 to 5 hours, preferably 0.1 to 4 hours, particularly preferably 0.5 to 3 hours.

If the polymerization temperature is high and the polymerization time is too long in order to obtain a polycarbonate resin having a predetermined molecular weight, the color tone tends to deteriorate. In particular, in order to suppress coloring and thermal deterioration of the polycarbonate resin and obtain a polycarbonate resin having a good hue and a low content of the compound represented by the above formula (3), the maximum internal temperature in all reaction stages is 240 ° C. Less than, especially preferably 210-235 ° C.

Further, when the internal temperature in all the reaction stages is 210 ° C. or higher and lower than 240 ° C., the reaction time is less than 3 hours, so that coloring and thermal deterioration of the polycarbonate resin can be suppressed, and a polycarbonate resin having a good hue can be obtained. It is preferable because the amount of the compound represented by the above formula (3) can be controlled, and it is particularly preferably within 2.5 hours.

Further, in order to suppress a decrease in the polymerization rate in the latter half of the polymerization reaction and minimize deterioration due to thermal history, it is excellent in plug flow property and interface renewal property at the final stage of polymerization, and is represented by the above formula (3). It is preferable to use a horizontal reactor having excellent control of the compound.

From the viewpoint of effective resource utilization, the by-produced monohydroxy compound is preferably purified as necessary and then reused as a raw material for diphenyl carbonate, bisphenol A, and the like.

As described above, the polycarbonate resin in the present invention is polycondensed, usually cooled and solidified, and pelletized with a rotary cutter or the like. The method of pelletization is not limited, but it is extracted from the final polymerization reactor in a molten state, cooled and solidified in the form of strands to be pelletized, and uniaxially or biaxially extruded from the final polymerization reactor in a molten state. The resin is supplied to the machine, melt-extruded, then cooled and solidified to be pelletized, or extracted from the final polymerization reactor in a molten state, cooled and solidified in the form of strands, once pelletized, and then uniaxial again. Alternatively, a method in which a resin is supplied to a twin-screw reactor, melt-extruded, and then cooled and solidified to be pelletized can be mentioned.

When an extruder is used, in the extruder, the residual monomer is volatilized under reduced pressure, and commonly known heat stabilizers, neutralizers, ultraviolet absorbers, light stabilizers, mold release agents, colorants, and antistatic agents are used. , Lubricants, lubricants, plasticizers, compatibilizers, flame retardants and the like can be added and kneaded.

The melt-kneading temperature in the extruder depends on the glass transition temperature and the molecular weight of the polycarbonate resin, but is usually 200 to 300 ° C, preferably 210 to 280 ° C, and more preferably 220 to 270 ° C. When the melt-kneading temperature is lower than 200 ° C., the melt viscosity of the polycarbonate resin is high, the load on the extruder is increased, and the productivity is lowered. If the melt-kneading temperature is higher than 300 ° C., the heat deterioration of the polycarbonate resin becomes severe, which causes a decrease in mechanical strength due to a decrease in molecular weight, coloring, and generation of bubbles due to generation of gas during film molding.

The molecular weight of the polycarbonate resin in the present invention thus obtained can be expressed by the reduced viscosity. The reduced viscosity is usually 0.30 dL / g or more, preferably 0.35 dL / g or more. The upper limit of the reduction viscosity is usually 1.20 dL / g or less, preferably 1.00 dL / g or less, and more preferably 0.80 dL / g or less.

If the reducing viscosity of the polycarbonate resin is too low, the mechanical strength of the molded product may be small. On the other hand, if the reducing viscosity is too large, the fluidity during molding tends to decrease, and the productivity and moldability tend to decrease. The reduced viscosity of the polycarbonate resin was measured by using methylene chloride as a solvent, precisely adjusting the polycarbonate resin concentration to 0.6 g / dL, and using an Ubbelohde viscous tube at a temperature of 20.0 ° C. ± 0.1 ° C. To. Details of the method for measuring the reduced viscosity will be described in the section of Examples.

[Polycarbonate resin additive]
<Phosphorus compound>
The polycarbonate resin in the present invention preferably contains a phosphorus-based compound added to inactivate the polymerization catalyst and further suppress the coloring of the polycarbonate resin at a high temperature.

The phosphorus-based compound is at least one selected from the group consisting of phosphoric acid, phosphite, hypophosphite, polyphosphoric acid, phosphonic acid, phosphonic acid ester, acidic phosphoric acid ester, and aliphatic cyclic phosphite ester. It is preferable to use seeds. Among the above, phosphorous acid, phosphonic acid, and phosphonic acid ester are more excellent in the effects of catalytic deactivation and color suppression, and phosphonic acid ester is particularly preferable.

Phosphonates include phosphonic acid (phosphoric acid), methylphosphonic acid, ethylphosphonic acid, vinylphosphonic acid, decylphosphonic acid, phenylphosphonic acid, benzylphosphonic acid, aminomethylphosphonic acid, methylenediphosphonic acid, 1-hydroxyethane- Examples thereof include 1,1-diphosphonic acid, 4-methoxyphenylphosphonic acid, nitrilotris (methylenephosphonic acid), and propylphosphonic acid anhydride.

Phosphonate esters include dimethyl phosphonate, diethyl phosphonate, bis (2-ethylhexyl) phosphonate, dilauryl phosphonate, diorail phosphonate, diphenyl phosphonate, dibenzyl phosphonate, dimethyl methylphosphonate, diphenyl methylphosphonate, ethylphosphonic acid. Diethyl, diethyl benzylphosphonate, dimethyl phenylphosphonate, diethyl phenylphosphonate, dipropyl phenylphosphonate, diethyl (methoxymethyl) phosphonate, diethyl vinylphosphonate, diethyl hydroxymethylphosphonate, dimethyl (2-hydroxyethyl) phosphonate, Diethyl p-methylbenzylphosphonate, diethylphosphonoacetic acid, ethyl diethylphosphonoacetate, tert-butyl diethylphosphonoacetate, diethyl (4-chlorobenzyl) phosphonate, diethyl cyanophosphonate, diethyl cyanomethylphosphonate, 3,5 Examples thereof include -di-tert-butyl-4-hydroxybenzylphosphonate diethyl, diethylphosphonoacetaldehyde diethylacetal, and (methylthiomethyl) phosphonate diethyl.

Examples of acidic phosphoric acid esters include dimethyl phosphate, diethyl phosphate, divinyl phosphate, dipropyl phosphate, dibutyl phosphate, bis (butoxyethyl) phosphate, bis (2-ethylhexyl) phosphate, diisotridecyl phosphate, and phosphoric acid. Phosphate diesters such as dioleyl, distearyl phosphate, diphenyl phosphate, dibenzyl phosphate, or a mixture of diester and monoester, diethyl chlorophosphate, stearyl phosphate zinc salt and the like can be mentioned.

Aliphatic cyclic phosphite ester is defined as a phosphite ester compound containing no aromatic group in a cyclic structure containing a phosphorus atom. For example, bis (decyl) pentaerythritol diphosphite, bis (tridecyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, bis (2,6-tert-butylphenyl) pentaerythritol diphosphite, bis (nonyl). Pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, Examples thereof include polymer-type compounds composed of dihydroxy compounds such as hydrogenated bisphenol A and pentaerythritol phosphite polymer and pentaerythritol diphosphite.

One of these may be used alone, or two or more thereof may be mixed and used in any combination and ratio.
If the content of the phosphorus compound is too small, the effect of catalyst deactivation and color suppression is insufficient. Further, if the content of the phosphorus-based compound is too large, the polycarbonate resin may be colored or coloring may occur under moist heat conditions. Therefore, the content of the phosphorus-based compound is not particularly limited, but the content of the phosphorus atom in the polycarbonate resin is preferably 0.02 wt ppm or more and 0.7 wt ppm or less, preferably 0.05 wt ppm or more. , 0.65 wt ppm or less is more preferable, and 0.07 wt ppm or more and 0.60 wt ppm or less are particularly preferable.

Since phosphorus trichloride is usually used as a starting material for the phosphorus compound, unreacted substances and desorbed hydrochloric acid-derived chlorine-containing components may remain, but the chlorine atom contained in the phosphorus compound may remain. The amount is preferably 5% by weight or less. If the residual amount of chlorine atoms is large, there is a concern that the metal part of the manufacturing facility to which the phosphorus compound is added may be corroded, the thermal stability of the polycarbonate resin may be lowered, and the molecular weight may be lowered due to coloring or thermal deterioration. is there.

As described above, the phosphorus compound is preferably added to and kneaded with the polycarbonate resin using an extruder. In particular, it is most effective to supply the polycarbonate resin to the extruder in a molten state after polymerization and immediately add the phosphorus compound to the resin. Further, if the devolatile treatment is performed by vacuum venting in an extruder with the catalyst deactivated, the low molecular weight components can be efficiently devolatile and removed.

<Hindered phenol compound>
By containing the hindered phenol compound in addition to the phosphorus compound in the polycarbonate resin in the present invention, further improvement in color tone of the polycarbonate resin can be expected.

Specific examples of the hindered phenol-based compound include 2,6-di-tert-butylphenol, 2,4-di-tert-butylphenol, 2-tert-butyl-4-methoxyphenol, and 2-tert-butyl-. 4,6-Dimethylphenol, 2,6-di-tert-butyl-4-methylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,5-di-tert-butylhydroquinone, n- Octadecyl-3- (3', 5'-di-tert-butyl-4'-hydroxyphenyl) propionate, 2-tert-butyl-6- (3'-tert-butyl-5'-methyl-2'-hydroxy Benzyl) -4-methylphenyl acrylate, 2,2'-methylene-bis- (4-methyl-6-tert-butylphenol), 2,2'-methylene-bis- (6-cyclohexyl-4-methylphenol), 2,2'-Etilidene-bis- (2,4-di-tert-butylphenol), tetrakis- [methylene-3- (3', 5'-di-tert-butyl-4'-hydroxyphenyl) propionate]- Methan, n-octadecyl-3- (3', 5'-di-tert-butyl-4'-hydroxyphenyl) propionate, 1,3,5-trimethyl-2,4,6-tris- (3,5-) Di-tert-butyl-4-hydroxybenzyl) benzene, triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3] -(3,5-Di-tert-butyl-4-hydroxyphenyl) propionate], pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] and the like.

One of these may be used alone, or two or more thereof may be mixed and used in any combination and ratio.
The content of the above-mentioned hindered phenol compound in the polycarbonate resin in the present invention is preferably 0.001 part by weight to 1 part by weight, preferably 0.005 part by weight to 0.5 part by weight, when the polycarbonate resin is 100 parts by weight. Is more preferable, and 0.01 part by weight to 0.3 part by weight is further preferable.
It is preferable that the hindered phenol compound and the following antioxidants are also added to and kneaded with the polycarbonate resin using an extruder in the same manner as the phosphorus compound.

<Antioxidant>
A commonly known antioxidant can also be added to the polycarbonate resin in the present invention for the purpose of preventing oxidation.
Specific examples of the antioxidant include triphenylphosphite, tris (nonylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tridecylphosphite, and trioctylphosphite. Trioctadecylphosphite, didecylmonophenylphosphite, dioctylmonophenylphosphite, diisopropylmonophenylphosphite, monobutyldiphenylphosphite, monodecyldiphenylphosphite, monooctyldiphenylphosphite, 2,2-methylenebis (4, 6-di-tert-butylphenyl) octyl phosphate, tris (2,4-di-tert-butylphenyl) phosphite, tributyl phosphate, triethyl phosphate, trimethyl phosphate, triphenyl phosphate, diphenyl monoorthoxenyl phosphate, dibutyl Phosphate, dioctyl phosphate, diisopropyl phosphate, 4,4'-biphenylenediphosphinate tetrakis (2,4-di-tert-butylphenyl), pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-laurylthio) Propionate), glycerol-3-stearylthiopropionate, N, N-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide), tris (3,5-di-) tert-butyl-4-hydroxybenzyl) isocyanurate, tetrakis 4,4'-biphenylenediphosphinate (2,4-di-tert-butylphenyl), 3,9-bis {1,1-dimethyl-2- [β] -(3-tert-Butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl} -2,4,8,10-tetraoxaspiro (5,5) undecane and the like.

One of these antioxidants may be used alone, or two or more thereof may be used in combination.
The blending amount of these antioxidants is preferably 0.0001 parts by weight to 0.1 parts by weight, more preferably 0.0005 parts by weight to 0.08 parts by weight, and 0, when the polycarbonate resin is 100 parts by weight. .001 parts by weight to 0.05 parts by weight is more preferable.

<Bluing agent>
The polycarbonate resin in the present invention may also contain a bluing agent.
The bluing agent used in the present invention may be appropriately selected from the bluing agents usually used in the polycarbonate resin composition and used by adjusting the blending amount thereof, and even if a plurality of types of bluing agents are used. Good.

The content of the brewing agent in the polycarbonate resin is usually preferably 0.1 × 10 ^{-4 to} 10.0 × 10 ^-4 parts by weight, more preferably 0, when the polycarbonate resin (A) is 100 parts by weight. .3 × 10 ^{-4 to} 5.0 × 10 ^-4 parts by weight, particularly preferably 0.3 × 10 ^{-4 to} 2.0 × 10 ^-4 parts by weight.

If the content of the bluing agent is 0.1 × 10 ^-4 parts by weight or more, the YI value before and after the accelerated light resistance test of the polycarbonate resin plate in the present invention should be within a specific range, and the b ^* value should be 3 It is preferable because the following can be easily performed. On the other hand, if the content of the bluing agent is 10.0 × 10 ^-4 parts by weight or less, the brightness does not decrease, and it is easy to set the L ^* value to 90 or more, which is preferable.

As the bluing agent used in the present invention, those used in the polycarbonate resin composition can be preferably used, but from the viewpoint of absorption wavelength, the maximum absorption wavelength is preferably 520 to 600 nm, more preferably 540. Dyes of ~ 580 nm are used.

Specific examples of the anthraquinone-based bluing agent preferable to be used in the present invention include, for example, the generic name Solvent Violet 13 [CA. No (Color Index No) 60725; Trademark name "Macrolex Violet B" manufactured by LANXESS, "Dialesin Blue G" manufactured by Mitsubishi Chemical Corporation, "Sumiplast Violet B" manufactured by Sumitomo Chemical Corporation], Solvent Violet14 , Generic name Solvent Coloret31 [CA. No68210; Trade name "Dialezin Violet D" manufactured by Mitsubishi Chemical Corporation], Solvent Violet33 [CA. No60725; Trade name "Diaresin Blue J" manufactured by Mitsubishi Chemical Corporation], Solvent Violet36 [CA. No68210; Trade name "Macrolex Violet 3R" manufactured by LANXESS], Solvent Blue45 [CA. No61110; Trademark name "Tetrazole Blue RLS" manufactured by Sand Co., Ltd.], generic name Solvent Blue94 [CA. No61500; Trade name "Dialesin Blue N" manufactured by Mitsubishi Chemical Corporation], Generic name Solvent Blue97 ["Macrlex Blue RR" manufactured by LANXESS], Generic name Solvent Blue45, Generic name SolvenBlue87 and Generic name Disperse Violet28. Be done.

Among these, the generic name Solvent Violet13 [Lanxess "Macrolex Violet B"], the generic name Solvent Violet36 [Lanxess "Macrolex Violet 3R"], and the generic name Solvent Blue97 [Lanxess "Macrolex Blue RR"" ] Is preferable, and the generic name Solvent Violet13 [“Macrex Violet B” manufactured by LANXESS Co., Ltd.] is more preferable.

Among them, in particular, a dye having a structure represented by the following formula (11), that is, the generic name Solvent Violet 13 [CA. No (color index No.) 60725; brand name "Macrolex Violet B" manufactured by LANXESS Corporation, "Dialesin Blue G" manufactured by Mitsubishi Chemical Corporation, and "Sumiplast Violet B" manufactured by Sumitomo Chemical Corporation] are preferable.

In the present invention, as the bluing agent, a pigment having a maximum absorption wavelength of preferably 520 to 600 nm, more preferably 540 to 580 nm can be used, and the above dye and pigment can be used in combination.
In the present invention, one type of bluing agent may be used alone or two or more types may be used in combination, but it is preferable that the amount of the bluing agent used is small, and the type of bluing agent used is also selected. Less is preferable.

In the present invention, the time and method of blending the above-mentioned bluing agent to be blended with the polycarbonate resin (A) are not particularly limited. As the compounding time, for example, a method of adding the raw material together with the raw material before the polymerization reaction and performing the polymerization as it is, a method of blending with a pipe or an extruder at the end of the polymerization reaction, and a method of blending when the polycarbonate resin is melt-kneaded with another compounding agent And so on. It is preferable to melt and knead after the completion of the polymerization reaction to improve the dispersion of the bluing agent and to easily adjust the b ^* value and the L ^* value at the same time. In particular, a method of introducing the melted state into an extruder after completion of the polycondensation reaction, blending a bluing agent, and melt-kneading the mixture is preferable because the influence of heat history and oxygen contamination can be minimized.

<UV absorber>
The ultraviolet absorber used in the present invention is not limited as long as it has the physical properties specified by the present invention and absorbs light in the ultraviolet wavelength region.
The melting point of the ultraviolet absorber used in the present invention is 135 ° C. or higher. Further, 140 ° C. or higher is more preferable, and 145 ° C. or higher is even more preferable.
Further, the melting point of the ultraviolet absorber used in the present invention is less than 300 ° C. Further, 290 ° C. or lower is more preferable, and 280 ° C. or lower is further preferable.

When the melting point is within this range, roll contamination and deposits on the T-die can be reduced during extrusion film formation, and the appearance of the film is improved. At the same time, when the ultraviolet absorber is kneaded by kneading with an extruder, the particles of the ultraviolet absorber are completely melted and uniformly dispersed, so that it is possible to prevent a film appearance defect caused by the particles of the ultraviolet absorber.

The 5% weight loss temperature of the UV absorber used in the present invention is higher than 240 ° C. Further, it is preferably higher than 245 ° C, more preferably higher than 250 ° C. Within this range, it is possible to prevent the ultraviolet absorber from being decomposed during melt-kneading. As a result, not only the ability of the ultraviolet absorber can be fully exhibited, but also the decomposition products accumulate in the extrusion vent to hinder continuous operation, and the decomposition products accumulate in the T-die, roll, etc., and the appearance of the film. Can be prevented from being damaged.

In the present invention, the ultraviolet absorber is contained in an amount of more than 0.45 parts by weight with respect to 100 parts by weight of the polycarbonate resin. Further, it is preferably contained in an amount of more than 0.47 parts by weight, and more preferably more than 0.5 parts by weight.
Within this range, the desired transmittance can be maintained in the ultraviolet region, and a desired effect can be obtained.

Further, the ultraviolet absorber is contained in an amount of 7 parts by weight or less with respect to 100 parts by weight of the polycarbonate resin. Further, it is more preferably contained in an amount of 5 parts by weight or less, and further preferably contained in an amount of 3 parts by weight or less. Within this range, not only the appearance deterioration of the film due to roll contamination can be prevented, but also the increase of foreign substances due to the aggregation of the ultraviolet absorber can be prevented.

When the ultraviolet absorber adheres to the roll, the unevenness is transferred to the film starting from the adhered substance, the film thickness cannot be kept uniform, and the resulting film causes uneven thickness and uneven phase difference. As for the thickness accuracy of the film, the thickness accuracy in the width direction varies depending on the required physical properties for each application, but is usually within ± 10%, preferably within ± 5%, and particularly preferably within ± 3%.

Further, when the melting point of the ultraviolet absorber is within the above range or the addition amount is within the above range, the glass transition temperature of the polycarbonate resin composition does not drop significantly after the addition of the ultraviolet absorber, and heat resistance can be maintained. .. The glass transition temperature of the composition is within 7 ° C., preferably within 5 ° C., and more preferably within 3 ° C. with respect to the glass transition temperature of the polycarbonate resin to which the ultraviolet absorber is not added.

Preferred ultraviolet absorbers include triazine-based, benzophenone-based, benzotriazole-based, quinolinone-based, benzoate-based, cyanoacrylate-based, and benzoxazole-based.

(Triazine UV absorber)
Examples of the triazine-based ultraviolet absorber include 2,4-diphenyl-6- (2-hydroxy-4-methoxyphenyl) -1,3,5-triazine and 2,4-diphenyl-6- (2-hydroxy-). 4-ethoxyphenyl) -1,3,5-triazine, 2,4-diphenyl- (2-hydroxy-4-propoxyphenyl) -1,3,5-triazine, 2,4-diphenyl- (2-hydroxy-) 4-Butoxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-butoxyphenyl) -1,3,5-triazine, 2,6-diphenyl-4- ( 2-Hydroxy-4-hexyloxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-octyloxyphenyl) -1,3,5-triazine, 2,4 −Diphenyl-6- (2-hydroxy-4-dodecyloxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-benzyloxyphenyl) -1,3,5 -Triazine, 2,4,6-tris (2-hydroxy-4-propoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-butoxyphenyl) -1,3 , 5-Triazine, 2,4,6-Tris (2-hydroxy-4-butoxyphenyl) -1,3,5-Triazine, 2,4,6-Tris (2-hydroxy-4-hexyloxyphenyl)- 1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-octyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-dodecyl) Oxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-benzyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy) -4-ethoxyethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-butoxyethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-Hydrazine-4-propoxyethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-methoxycarbonylpropyloxyphenyl) -1,3,5-triazine, 2, , 4,6-Tris (2-hydroxy-4-ethoxycarbonylethyloxyphenyl) -1,3,5-triazine, 2,4,6-Tris (2- Hydroxy-4- (1- (2-ethoxyhexyloxy) -1-oxopropan-2-yloxy) phenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl) -4-ethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-propoxyphenyl) -1,3,5-triazine, 2,4,6 -Tris (2-hydroxy-3-methyl-4-butoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-butoxyphenyl) -1,3 , 5-Triazine, 2,4,6-Tris (2-Hydroxy-3-methyl-4-hexyloxyphenyl) -1,3,5-Triazine, 2,4,6-Tris (2-Hydroxy-3- Methyl-4-octyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-dodecyloxyphenyl) -1,3,5-triazine, 2, 4,6-Tris (2-Hydroxy-3-methyl-4-benzyloxyphenyl) -1,3,5-triazine, 2,4,6-Tris (2-Hydroxy-3-methyl-4-ethoxyethoxyphenyl) ) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-butoxyethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2) -Hydroxy-3-methyl-4-propoxyethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-methoxycarbonylpropyloxyphenyl) -1,3 , 5-Triazine, 2,4,6-Tris (2-Hydroxy-3-methyl-4-ethoxycarbonylethyloxyphenyl) -1,3,5-Triazine, 2,4,6-Tris (2-Hydroxy- 3-Methyl-4- (1- (2-ethoxyhexyloxy) -1-oxopropan-2-yloxy) phenyl) -1,3,5-triazine, 2,4-bis (2,4-dimethylphenyl) -6- (2-Hydroxy-4-N-octyloxyphenyl) -1,3,5-triazine, 2- (4,6-diphenyl-1,3,5-triazine-2-yl) -5-( Examples thereof include 2- (2-ethylhexanoyloxy) ethoxy) phenol.

Among them, commercially available products include 2,4-bis (2,4-dimethylphenyl) -6- (2-hydroxy-4-N-octyloxyphenyl) -1,3,5-triazine (Chemiplo Kasei Co., Ltd.). "Kemisorb102"), 2,4,6-tris (2-hydroxy-3-methyl-4-hexyloxyphenyl) -1,3,5-triazine ("Adecastab LA-F70" manufactured by ADEKA Co., Ltd.), 2- (4,6-diphenyl-1,3,5-triazine-2-yl) -5-(2- (2-ethylhexanoyloxy) ethoxy) phenol ("Adecastab LA-46" manufactured by ADEKA Co., Ltd. ), 2,4-Diphenyl-6- (2-hydroxy-4-hexyloxyphenyl) -1,3,5-triazine (BASF Japan Co., Ltd. "Tinubin 1577").

(Benzophenone UV absorber)
Examples of the benzophenone-based ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, and 2-hydroxy-. 4-Meth-5-sulfoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfoxitrihydride benzophenone, 2-hydroxy-4-dodecyloxy-benzophenone, 2-hydroxy-4-octadeciloxy-benzophenone, 2 , 2'-Dihydroxy-4-methoxybenzophenone, 2,2', 4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4,4 '-Dimethoxy-5-sodium sulfoxybenzophenone, bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) methane, 2-hydroxy-4-n-dodecyloxybenzophenone, 2-hydroxy-4-methoxy Examples thereof include -2'-carboxybenzophenone and 4,4'-bis (diethylamino) benzophenone.

Among them, commercially available products include 2,2', 4,4'-tetrahydroxybenzophenone ("Seasorb 106" manufactured by Cipro Chemical Co., Ltd., "Uvinul3050" manufactured by BASF Japan Ltd.), 2,2'-dihydroxy-. Examples thereof include 4,4'-dimethoxybenzophenone ("Seasorb 107" manufactured by Cipro Chemical Co., Ltd. and "Uvinul3049" manufactured by BASF Japan Ltd.).

(Benzotriazole UV absorber)
Examples of the benzotriazole-based ultraviolet absorber include 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- [2'-hydroxy-3', 2- (2'-hydroxy-3'-). tert-butyl-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 5'-bis (α, α-dimethylbenzyl) phenyl] -benzotriazole, 2- (2'-Hydroxy-3', 5'-di-tert-butyl-phenyl) -benzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzo Triazole, 2- (2'-hydroxy-3', 5'-di-tert-butyl-phenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3', 5'-di-tert-amyl) ) -Benzotriazole, 2- (2'-hydroxy-3', 5'-di-tert-amylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-(3 ", 4" , 5 ", 6" -tetrahydrophthalimidemethyl) -5'-methylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-tert-pentylphenyl), 2- (2'-hydroxy-5' -Tart-octylphenyl) benzotriazole, 2,2'-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazole-2-yl) phenol] and the like can be mentioned. ..

Among them, as a commercially available product, 2,2'-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazole-2-yl) phenol] (manufactured by ADEKA Corporation) "ADEKA STAB LA-31", "Kemisorb 279" manufactured by Chemipro Chemical Co., Ltd.), 2- (2'-hydroxy-5'-tert-octylphenyl) benzotriazole ("Seasorb 709" manufactured by Cipro Chemical Co., Ltd.) Be done.

(Indole UV absorber)
As the indole-based ultraviolet absorber, a compound represented by the following formula (12) can be used, for example, 2-[(1-methyl-2-phenyl-1H-indole-3-yl) methylene] propandi. Examples thereof include nitrile (“BONASORB UA-3901” manufactured by Orient Chemical Industry Co., Ltd.).

In the above formula (12), R _{1 to} R ₃ represent arbitrary substituents. However, R ₂ and R ₃ may be substituted at one or a plurality of locations, and when substituting a plurality of locations, the respective substituents may be the same or different.

(Quinoline UV absorber)
As the quinolinone-based ultraviolet absorber, a compound represented by the following formula (13) can be used, for example, 4-hydroxy-3-[(phenylimino) methyl] -2 (1H) -quinolinone (orientate). "BONASORB UA-3701") manufactured by Chemical Industry Co., Ltd.) and the like.

In the above formula (13), R _{4 to} R ₆ represent arbitrary substituents. However, R ₅ and R ₆ may be substituted at one place or a plurality of places, and when substituting a plurality of places, the respective substituents may be the same or different.

(Benzoate UV absorber)
Examples of the benzoate-based ultraviolet absorber include 2,4-di-t-butylphenyl-3', 5'-di-t-butyl-4'-hydroxybenzoate, and 2,6-di-t-butylphenyl-. 3', 5'-di-t-butyl-4'-hydroxybenzoate, n-hexadecyl-3,5-di-t-butyl-4-hydroxybenzoate, n-octadecyl-3,5-di-t-butyl -4-Hydroxybenzoate and the like can be mentioned. These benzoate-based ultraviolet absorbers can be used as ultraviolet absorbers.

(Cyanoacrylate UV absorber)
Examples of the cyanoacrylate-based ultraviolet absorber include 2'-ethylhexyl-2-cyano-3,3-diphenylacrylate, ethyl-2-cyano-3- (3', 4'-methylenedioxyphenyl) -acrylate and the like. Can be mentioned. These cyanoacrylate-based ultraviolet absorbers can be used as ultraviolet absorbers.
In the present invention, the ultraviolet absorber may be used alone or in combination of two or more.
Among these, triazine-based, benzotriazole-based, quinolinone-based, and indole-based are preferable from the viewpoint of thermal stability and less coloring of the resin.

(Other UV absorbers)
In addition to the above-mentioned ultraviolet absorbers, fluorescent whitening agents can also be used as other ultraviolet absorbers. For example, 7- (dimethylamino) -4-methylcoumarin and benzoxazole-based 2,5-bis (5-tert-butyl-2-benzoxazolyl) thiophene (BASF Japan Ltd. "TINOPAL OB") , 4,4'-bis (2-benzoxazolyl) stilbene and the like. Of these, the benzoxazole type is preferable.

[Polycarbonate resin composition]
The polycarbonate resin composition in the present invention includes, for example, aromatic polycarbonate resin, aromatic polyester, aliphatic polyester, polyamide, polystyrene, polyolefin, acrylic, amorphous polyolefin, synthetic resin such as ABS, AS, polylactic acid, polybutylene succinct. It can also be used as a polymer alloy by kneading with one or more kinds of biodegradable resins such as nate and rubber.

Further, the polycarbonate resin used in the present invention is a nucleating agent, a flame retardant, a flame retardant aid, an inorganic filler, an impact improver, a hydrolysis inhibitor, and a foaming agent which are usually used in a resin composition together with these other resin components. , Dyeing pigment and the like can be added to obtain a polycarbonate resin composition.

[Manufacturing method of extruded polycarbonate resin]
<Manufacturing method>
The polycarbonate resin film of the present invention is a film obtained by molding a resin composition containing the polycarbonate resin used in the present invention, an ultraviolet absorber, and if necessary, other additives according to a conventional method. The method for producing the polycarbonate resin film is preferably a melt extrusion molding method such as a T-die molding method or an inflation molding method, and particularly preferably a T-die molding method.

When the polycarbonate resin film of the present invention is placed on the front surface or the back surface of an image display device, the displayed image must not be damaged by defects, distortion, or the like and visually recognized. Therefore, when the film is formed by the melt extrusion molding method, there are very few defects of foreign substances derived from resin such as gel, air bubbles, and burn, and the thickness is uniform in the width direction and there is no optical distortion such as local phase difference. Is required.

The resin temperature during melt extrusion is usually in the range of 150 to 265 ° C, preferably 200 ° C to 260 ° C, and particularly preferably 210 ° C to 250 ° C. If the temperature is lower than the above temperature, the melt viscosity tends to be too high and the extrusion load tends to be high. On the other hand, when the temperature is higher than the above temperature, at least the polycarbonate resin in the resin composition begins to thermally decompose, causing deterioration phenomena such as coloring and decrease in viscosity.

After controlling the resin temperature so that the melt viscosity is appropriate for molding, the resin extrusion is rectified by mutually feedback-controlling the discharge amount of the raw material feeder, the screw rotation speed of the extruder, the liquid feed amount of the gear pump, etc. Therefore, the thickness accuracy of the film can be improved. The thickness accuracy in the width direction varies depending on the required physical properties for each application, but is usually within ± 10%, preferably within ± 5%, and particularly preferably within ± 3%.

The thickness measurement in the width direction is evaluated at each measurement point when there is a traverse type continuous thickness measuring machine in the continuous film forming line. When performing offline measurement with a cut film, it is evaluated by measuring with a dial gauge thickness gauge or the like at intervals of 50 mm in the width direction. Here, since both ends of the extruded film are thickened due to neck-in or the like, the evaluation is performed in the width direction range excluding the portion to be slit and discarded.

The cooling roll temperature is preferably Tg-100 ° C. to Tg + 50 ° C., more preferably Tg-80 ° C. to Tg + 40 ° C., and particularly preferably Tg-60, relative to the glass transition temperature (Tg) of the polycarbonate resin composition. ° C to Tg + 30 ° C. More specifically, the cooling roll temperature is preferably 20 to 170 ° C, more preferably 40 to 160 ° C, and particularly preferably 60 to 150 ° C.

When the cooling roll temperature is lower than the above temperature, gear marks are formed on the film surface and local optical strain unevenness becomes remarkable. On the other hand, when the temperature is higher than the above temperature, the extruded film is difficult to peel off from the cooling roll, which tends to cause peeling marks or contaminate the roll.

Further, the polycarbonate resin film in the present invention may be a stretched film, and can be made into a retardation film by stretching in at least one direction.
As the stretching method, various stretching methods such as free-end stretching, fixed-end stretching, free-end contraction, and fixed-end contraction can be used alone, or simultaneously or sequentially. Further, the stretching direction can be performed in various directions and dimensions such as a horizontal direction, a vertical direction, a thickness direction, and a diagonal direction, and is not particularly limited. Preferably, a horizontal uniaxial stretching method, a vertical / horizontal simultaneous biaxial stretching method, a vertical / horizontal sequential biaxial stretching method, and the like can be mentioned.

As the stretching means, any suitable stretching machine such as a tenter stretching machine and a biaxial stretching machine can be used.
An appropriate value can be appropriately selected for the stretching temperature according to the purpose. Preferably, the stretching is Tg-20 ° C. to Tg + 30 ° C., preferably with respect to the glass transition temperature (Tg) of the raw film (that is, the polycarbonate or the resin composition thereof in the present invention which is the film-forming material of the raw film). Is carried out in the range of Tg-10 ° C. to Tg + 20 ° C., more preferably Tg-5 ° C. to Tg + 10 ° C. By selecting such a condition, the retardation value is likely to be uniform, and the film is less likely to become cloudy. Specifically, the stretching temperature is 90 ° C. to 210 ° C., more preferably 100 ° C. to 200 ° C., and particularly preferably 100 ° C. to 180 ° C.

The draw ratio is appropriately selected according to the purpose, and the unstretched case is set to 1 time, preferably 1.1 times or more and 6 times or less, more preferably 1.5 times or more and 4 times or less, still more preferably 1.8. It is doubling or more and 3 times or less, and particularly preferably 2 times or more and 2.5 times or less.

If the draw ratio is excessively large, not only breakage during stretching may occur, but also the effect of suppressing fluctuations in optical characteristics due to long-term use under high temperature conditions may be reduced. There is a possibility that the intended optical characteristics cannot be imparted in terms of thickness.

The stretching speed is also appropriately selected depending on the intended purpose, but the strain rate represented by the following formula is usually 50% to 2000%, preferably 100% to 1500%, more preferably 200% to 1000%, and particularly preferably 250. % To 500%. If the stretching speed is excessively high, it may cause breakage during stretching, or the optical characteristics may fluctuate greatly due to long-term use under high temperature conditions. Further, if the stretching speed is excessively low, not only the productivity is lowered, but also the stretching ratio may have to be excessively increased in order to obtain a desired phase difference.
Strain rate (% / min) = {stretching rate (mm / min) / length of raw film (mm)} x 100
Further, the heat fixing treatment may be performed in a heating furnace after stretching, or the relaxation step may be performed by controlling the width of the tenter or adjusting the peripheral speed of the roll.

By performing this treatment, fluctuations in optical characteristics due to long-term use under high temperature conditions can be suppressed.
The film of the present invention can be produced by appropriately selecting and adjusting the treatment conditions in such a stretching step.

The upper limit of the thickness of the film of the present invention is 120 μm or less. It is more preferably 50 μm or less, and further preferably 30 μm or less. When the upper limit of the thickness of the film is within this range, it is efficient because a film having the same area can be produced with a smaller amount of film-forming material. Furthermore, the thickness of the product using the film can be maintained thin, and the uniformity can be controlled, which is useful for equipment that requires precision, thinness, and homogeneity.

On the other hand, the lower limit of the thickness of the film of the present invention is 5 μm or more. It is preferably 10 μm or more. If the thickness of the film is excessively thin, it becomes extremely difficult to handle the film, wrinkles may occur during manufacturing, or it may be difficult to attach the film to another film such as a protective film or a sheet. When the lower limit of the thickness of the film of the present invention is within this range, such a problem can be solved.

The film of the present invention can be used as a polarizer protective film, and may be a hard coat layer, an antireflection treatment, an anti-sticking treatment, or a treatment for the purpose of diffusion or anti-glare, and the surface may be treated before bonding. As the treatment, a corona discharge treatment, an ultraviolet irradiation treatment, or the like may be applied.

The film of the present invention has a lower limit of light transmittance of 0.001% or more at a wavelength of 380 nm. 0.005% or more is preferable, 0.008% or more is more preferable, and 0.01% or more is further preferable. If the transmittance is too low, the content of the ultraviolet absorber inevitably increases, which may cause poor appearance of the film.

Further, the film of the present invention has an upper limit of light transmittance of 15% or less at a wavelength of 380 nm. 8% or less is preferable, 1% or less is more preferable, and 0.1% or less is further preferable. If the transmittance is too high, the polarizer may be deteriorated by ultraviolet rays when used as a polarizer protective film.

When the film of the present invention is used as a retardation film, the in-plane retardation at 548 nm is preferably 100 nm or more, more preferably 110 nm or more, still more preferably 120 nm or more.

Further, it is preferably 200 nm or less, more preferably 180 nm or less, and further preferably 160 nm or less. When the in-plane phase difference is within this range, the quality of the image of the polarizing plate or the image display device obtained by using the present invention becomes extremely clear and good. Specifically, when the polarizing plate or the image display device obtained by using the present invention is observed through polarized sunglasses, a rainbow pattern or the like caused by a change in the visual angle is unlikely to occur.

<Foreign matter on film>
The generation of foreign matter on the film not only impairs the quality of the film, but is also not preferable from the viewpoint of film productivity. As described above, the reduction of foreign matter in the film is caused by reducing the content of a specific compound in the resin composition, generating unmelted substances during melt-kneading, and bleeding out during film formation. It is particularly effective to prevent the formation of film-forming roll stains.

The foreign matter in the film is evaluated by the method described later, but 15 pieces / m ² or less is preferable, 10 pieces / m ² or less is more preferable, 5 pieces / m ² or less is further preferable, and 3 pieces / m ² or less. Is particularly preferable. If there is a foreign substance exceeding this value, not only the appearance of the film is impaired, but also the optical properties of the film are significantly affected.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples as long as the gist thereof is not exceeded.
[Evaluation method]
In the following, the physical properties or properties of the polycarbonate resin were evaluated by the following method.

(1) Measurement of Reduction Viscosity A polycarbonate resin sample was dissolved in methylene chloride to prepare a polycarbonate resin solution having a concentration of 0.6 g / dL. Measurement was performed at a temperature of 20.0 ° C. ± 0.1 ° C. using a Ubbelohde type viscosity tube manufactured by Moriyu Rika Kogyo Co., Ltd., and the relative viscosity η from the following equation (i) was obtained from the solvent passage time t ₀ and the solution passage time t. _{The rel} was determined, and the specific viscosity η _sp was determined from the relative viscosity η _rel from the following equation (ii).
η _reel = t / t ₀ ... (i)
η _sp = (η − η ₀ ) / η ₀ = η _reel -1 ・ ・ ・ (ii)
The specific viscosity η _sp was divided by the concentration c (g / dL) to obtain the reduced viscosity η _sp / c. The higher this value, the larger the molecular weight. The larger the value of the reducing viscosity, the more excellent the mechanical strength of the film can be obtained.

(2) Ultraviolet transmittance at 380 nm The light transmittance at a wavelength of 380 nm was measured using an ultraviolet-visible spectrophotometer (U2900 manufactured by Hitachi High-Technologies Corporation) in accordance with JIS K0115 (2004) (general rules for absorptiometry). ..

(3) 5% weight loss temperature Measurement was performed with TG-DTA6300 (manufactured by Seiko) under nitrogen (flow rate 200 ml / min) while raising the temperature of about 10 mg of the sample from room temperature to 500 ° C. at 10 ° C./min. The 5% weight loss temperature was determined.

(4) Melting point Measured using a differential scanning calorimeter (DSC6220 manufactured by SII Nanotechnology). Approximately 10 mg of the sample was placed in the company's aluminum pan and sealed, and the temperature was raised from room temperature to 400 ° C. at a heating rate of 10 ° C./min under a nitrogen stream of 50 mL / min, and the temperature at the peak of the melting peak was determined and used as the melting point. ..

(5) Glass transition temperature (Tg) of polycarbonate resin
The glass transition temperature of the polycarbonate resin was measured using a differential scanning calorimeter (DSC6220 manufactured by SII Nanotechnology). Approximately 10 mg of a polycarbonate resin sample was placed in an aluminum pan manufactured by the same company, sealed, and heated from room temperature to 250 ° C. at a heating rate of 20 ° C./min under a nitrogen stream of 50 mL / min. After maintaining the temperature for 3 minutes, it was cooled to 0 ° C. at a rate of 20 ° C./min. The temperature was maintained at 0 ° C. for 3 minutes, and the temperature was raised again to 200 ° C. at a rate of 20 ° C./min. From the DSC data obtained by the second temperature rise, the extrapolation glass transition start temperature was adopted.

(6) Measurement of the content of phenol and the compound represented by the formula (3) About 1 g of a polycarbonate resin sample is precisely weighed and dissolved in 5 mL of methylene chloride to make a solution, and then acetone is added so that the total amount becomes 25 mL. It was added and reprecipitated. Then, the treatment liquid was filtered through a 0.2 μm disc filter, and quantification was performed by liquid chromatography.

(7) Film molding and roll stain evaluation At 2 kg / Hr, OCS gel counter FSA film inspection line (barrel set temperature: 240 ° C, T die (width 150 mm, set temperature: 240 ° C), chill roll (set temperature: 105) A film was formed with each thickness at ° C.)), and the presence or absence of roll stain was determined according to the following criteria.

Roll stains could be visually confirmed in 0 to less than 15 minutes: XX
Roll stains could be visually confirmed in 15 minutes or more and less than 30 minutes: ×
Roll stains visually confirmed in 30 minutes or more and less than 60 minutes: △ ^-
Roll stains could be visually confirmed in 60 minutes or more and less than 90 minutes: △
Roll stains could be visually confirmed in 90 minutes or more and less than 120 minutes: ○ ⁻
Roll stains could be visually confirmed in 120 minutes or more and less than 150 minutes: ○
Roll stains could be visually confirmed in 150 minutes or more and less than 180 minutes: ◎

(8) Film thickness and thickness accuracy About 10 m from the start of film income, a contact thickness gauge (manufactured by Ono Sokki Co., Ltd.) product name "Digital" covers a range of 30 mm from the center of the film in both width directions at 10 mm intervals in the TD direction. The thickness of the film was measured using a linear gauge DG-933 "). Here, the "film thickness" referred to in the present invention is a calculation of the total average of the measured values. Further, the numerical value obtained from the following formula was defined as "thickness accuracy" in the present invention.
Thickness accuracy (%) = {(maximum deviation from film thickness) / (film thickness)} x 100
(However, the "maximum deviation from the film thickness" in the formula means the maximum value among the differences between each of the above measured values and the average value (film thickness).)
The smaller the value of the thickness accuracy, the more uniform the thickness of the film.

(9) Foreign matter on film With respect to a sample cut out from the obtained film to a width of 50 mm and a length of 200 mm, the number of foreign matter having a diameter (major diameter in the case of an ellipse) of 150 μm or more in the sample was visually counted. The smaller the number of foreign substances present, the better the film when used for, for example, an optical film.

[Ingredients used]
The abbreviations and manufacturers of the compounds used in the following examples and comparative examples are as follows.

<Dihydroxy compound>
・ ISB: Isosorbide [Rocket Foil]
CHDM: 1,4-Cyclohexanedimethanol [manufactured by SK Chemical]
-TCDDM: Tricyclodecanedimethanol [manufactured by OXEA]
<Carbonate diester>
・ DPC: Diphenyl carbonate [manufactured by Mitsubishi Chemical Corporation]
<Hindered phenol compound>
-Irganox 1010: Pentaerythritol-Tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] [manufactured by BASF Japan Ltd.]

<Phosphorus compound>
-Phosphorous acid [manufactured by Taihei Chemical Industry Co., Ltd.] (molecular weight 82.0)
AS2112: Tris (2,4-di-tert-butylphenyl) phosphite [manufactured by ADEKA Corporation] (molecular weight 646.9)

<UV absorber>
-UVA-1: LA-31 [manufactured by ADEKA Corporation]
-UVA-2: LA-36 [manufactured by ADEKA Corporation]
-UVA-3: LA-F70 [manufactured by ADEKA Corporation]
-UVA-4: BONASORB UA-3701 [manufactured by Orient Chemical Industry Co., Ltd.]
-UVA-5: Uvinul3049 [manufactured by BASF Japan Ltd.]
-UVA-6: Uvinul3050 [manufactured by BASF Japan Ltd.]
-UVA-7: Seesorb709 [manufactured by Cipro Kasei Co., Ltd.]
-UVA-8: Tinuvin234 [manufactured by BASF Japan Ltd.]
・ UVA-9: TINOVAL OB [manufactured by BASF Japan Ltd.]
-UVA-10: Cyber UV-5411 [manufactured by Cytec Industries, Ltd.]
The physical properties of the UV absorber are summarized in Table 1 below.

Polycarbonate resin manufacturing method
[Manufacturing Example 1]
The polycarbonate resin was polymerized using a continuous polymerization facility consisting of three vertical stirring reactors, one horizontal stirring reactor, and a twin-screw extruder. ISB, CHDM and DPC were each melted in a tank and continuously supplied to the first vertical stirring reactor at a molar ratio of ISB / CHDM / DPC = 0.700 / 0.300 / 1.010. At the same time, an aqueous solution of calcium acetate monohydrate was supplied to the first vertical stirring reactor as a catalyst so as to be 1.5 μmol with respect to 1 mol of the total dihydroxy compound. The liquid level was kept constant while controlling the opening degree of the valve provided in the transfer pipe at the bottom of the reactor so that the average residence time in the first vertical stirring reactor was 90 minutes. The reaction solution discharged from the bottom of the reactor continues to the 2nd vertical stirring reactor, the 3rd vertical stirring reactor, and the 4th horizontal stirring reactor [2-axis glasses blade manufactured by Hitachi Plant Technologies, Ltd.]. Continuously supplied. The first vertical stirring reactor and the second vertical stirring reactor were provided with a reflux condenser, and the distillation of unreacted dihydroxy compounds and DPC was suppressed by adjusting the reflux ratio.

The reaction temperature, internal pressure, and residence time of each reactor are as follows: 1st vertical stirring reactor: 190 ° C., 25kPa, 90 minutes, 2nd vertical stirring reactor: 195 ° C., 10kPa, 45 minutes, 3rd vertical type. Stirring reactor: 210 ° C., 3 kPa, 45 minutes, 4th horizontal stirring reactor: 230 ° C., 0.5 kPa, 90 minutes. The operation was performed while finely adjusting the internal pressure of the fourth horizontal stirring reactor so that the reduced viscosity of the obtained polycarbonate resin was changed from 0.61 dL / g to 0.64 dL / g.

The polycarbonate resin was continuously extracted from the fourth horizontal stirring reactor, and then the resin was supplied to a twin-screw extruder [TEX30α manufactured by Japan Steel Works, Ltd.] in a molten state. The extruder has three vacuum vent ports, and the residual low molecular weight components in the resin are volatilized and removed. A master pellet sprinkled with phosphorous acid is supplied from the front of the first vent port, 0.65 ppm of phosphorous acid (0.2 ppm as the amount of phosphorus atom) is added to the polycarbonate resin, and before the second vent. 2000 wt ppm of water was added to the resin to perform water injection devolatileization, and 500 ppm of AS2112 and 1000 ppm of Irganox 1010 were supplied from the front of the third bench. For the extruder (10 barrels in total), the cylinder temperature was set to 220 ° C. and the screw rotation speed was set to 230 rpm. The resin temperature at the extruder outlet was 262 ° C.
The polycarbonate resin that passed through the extruder was continuously filtered through a filter in a molten state, discharged from the die in a strand shape, water-cooled and solidified, and then pelletized with a rotary cutter. The glass transition temperature of the pellet was 122 ° C. The obtained polycarbonate resin is referred to as PC1.

[Manufacturing Example 2]
A polycarbonate resin was obtained in the same manner as in Example 1 except that the molar ratio ISB / CHDM / DPC = 0.700 / 0.300 / 1.012 and the mixture was continuously supplied to the first vertical stirring reactor. The glass transition temperature of the pellet was 122 ° C. The obtained polycarbonate resin is referred to as PC2.

[Manufacturing Example 3]
The first vertical is such that the molar ratio ISB / CHDM / DPC = 0.700 / 0.300 / 1.000 and the aqueous solution of calcium acetate monohydrate as a catalyst is 1.25 μmol with respect to 1 mol of the total dihydroxy compound. The reaction temperature, internal pressure, and residence time of each reactor are continuously supplied to the type stirring reactor, respectively, 1st vertical type stirring reactor: 188 ° C., 24.2 kPa, 90 minutes, 2nd vertical type stirring reactor. 194 ° C, 19.9 kPa, 60 minutes, 3rd vertical stirring reactor: 214 ° C, 9.9 kPa, 60 minutes, 4th horizontal stirring reactor: 225 ° C, 0.1 kPa, 120 minutes, the extruder The cylinder temperature was set to 240 ° C. for the first four barrels, 195 ° C. for the latter six barrels, and the screw rotation rate was set to 225 rpm in the same manner as in Example 1. The glass transition temperature of the pellet was 122 ° C. The obtained polycarbonate resin is designated as PC3.

[Manufacturing Example 4]
The polycarbonate resin was polymerized using a batch polymerization facility consisting of a vertical stirring reactor and a twin-screw extruder. ISB, CHDM and DPC were melted in tanks, respectively, and ISB was supplied to the first vertical stirring reactor at a molar ratio of ISB / CHDM / DPC = 0.700 / 0.300 / 1.000. At the same time, an aqueous solution of cesium carbonate was supplied to the first vertical stirring reactor as a catalyst so that the amount of cesium carbonate was 1.25 μmol with respect to 1 mol of the total dihydroxy compound. As the first step of the reaction, the heating tank temperature is heated to 150 ° C., the raw material is dissolved for 15 minutes while stirring, the pressure is reduced from normal pressure to 13.3 kPa in 40 minutes, and the heating tank temperature is adjusted. The generated phenol was extracted from the reaction vessel while raising the temperature to 190 ° C. in 40 minutes. After holding the entire reaction vessel at 190 ° C. for 15 minutes, the heating tank temperature was raised to 240 ° C. in 30 minutes as the second step. Ten minutes after the temperature was raised, the pressure in the reaction vessel was reduced to 0.200 kPa or less in 30 minutes, and the generated phenol was distilled out. After 120 minutes, after reaching the predetermined stirring torque, the reaction is stopped, the polycarbonate resin is continuously withdrawn from the reactor, and then the twin-screw extruder with the resin in a molten state [TEX30α manufactured by Japan Steel Works, Ltd.] Supplied to. The extruder has three vacuum vent ports, and the residual low molecular weight components in the resin are volatilized and removed. A master pellet sprinkled with phosphorous acid is supplied from the front of the first vent port, 0.65 ppm of phosphorous acid (0.2 ppm as the amount of phosphorus atom) is added to the polycarbonate resin, and before the second vent. 2000 wt ppm of water was added to the resin to perform water injection devolatileization, and 500 ppm of AS2112 and 1000 ppm of Irganox 1010 were supplied from the front of the third bench. The extruder (10 barrels in total) set the cylinder temperature to 220 ° C. and the screw rotation speed to 230 rpm. The resin temperature at the extruder outlet was 261 ° C.
The polycarbonate resin that passed through the extruder was continuously filtered through a filter in a molten state, discharged from the die in a strand shape, water-cooled and solidified, and then pelletized with a rotary cutter. The glass transition temperature of the pellet was 122 ° C. The obtained polycarbonate resin is designated as PC4.

The amounts of phenol contained in the polycarbonate resin and the compound represented by the formula (3) are collectively shown in Table 2 below.

[Example 1]
A twin-screw extruder with a vent (TEX30α manufactured by Japan Steel Works, Ltd.) using a quantitative feeder to 100 parts by weight of the polycarbonate resin (PC1) and 1.5 parts by weight of UVA-1 described in Production Example 1, and the cylinder set temperature. : 240 ° C.), the foreign matter was filtered through a filter, discharged from the die in a strand shape, water-cooled and solidified, and then pelletized with a rotary cutter.

Then, the polycarbonate resin composition was subjected to an OCS gel counter FSA film inspection line (barrel set temperature: 240 ° C., T die (width 150 mm, set temperature: 240 ° C.)), chill roll (set temperature: 105 ° C.) at 2 kg / Hr. )), A film having a thickness of 40 μm was extruded. The results are shown in Table 3 below.

[Examples 2 to 13, Comparative Examples 1 to 5]
As shown in Table 3 below, the same procedure as in Example 1 was carried out except that the thickness of the film, the type of the ultraviolet absorber and the amount of the ultraviolet absorber were changed.

The films of Examples 1 to 13 were particularly excellent films because the numerical value of the thickness accuracy was particularly small and the film had a uniform thickness, and at the same time, the amount of foreign matter in the film per unit area was small.

On the other hand, in Comparative Examples 1 to 5, the type and amount of the ultraviolet absorber used were considered to be caused by a decrease in heat resistance of the resin composition and roll stains caused by bleed-out, resulting in deterioration of film thickness accuracy. , The amount of foreign matter increased.
In Comparative Example 4 and Comparative Example 5, a large number of fine foreign substances were confirmed, although they were not foreign substances having a size of 150 μm or more, which are considered to have aggregated the ultraviolet absorber on the entire film due to unmelting.

[Examples 14 to 16]
As shown in Table 4 below, the same procedure as in Example 4 was carried out except that the polycarbonate resin used was changed from PC1 to PC2, PC3 or PC4.
The films of Examples 14 to 16 were particularly excellent films because the numerical value of the thickness accuracy was particularly small and the film had a uniform thickness, and at the same time, the amount of foreign matter in the film per unit area was small.

[Examples 17 to 19]
As shown in Table 5 below, the same procedure as in Example 6 was carried out except that the polycarbonate resin used was changed from PC1 to PC2, PC3 or PC4.
The films of Examples 17 to 19 were all particularly excellent films because the numerical value of the thickness accuracy was particularly small and the film had a uniform thickness, and at the same time, the amount of foreign matter in the film per unit area was small.

[Example 20]
A twin-screw extruder with a vent (TEX30α manufactured by Japan Steel Works, Ltd.) using a quantitative feeder to 100 parts by weight of the polycarbonate resin (PC1) and 1.2 parts by weight of UVA-3 described in Production Example 1, and the cylinder set temperature. : 240 ° C.), the foreign matter was filtered through a filter, discharged from the die in a strand shape, water-cooled and solidified, and then pelletized with a rotary cutter.

Then, the polycarbonate resin composition was subjected to an OCS gel counter FSA film inspection line (barrel set temperature: 240 ° C., T die (width 150 mm, set temperature: 240 ° C.)), chill roll (set temperature: 105 ° C.) at 2 kg / Hr. )), A film having a thickness of 50 μm was extruded. An unstretched film with a length of 125 mm and a width of 50 mm is cut out from this film and fixed with a batch-type biaxial stretching device (manufactured by Island Industry Co., Ltd.) at a strain rate of 5 mm / min, a stretching temperature of 134 ° C., and a stretching ratio of 1.8 times. End-uniaxial stretching was performed. A sample obtained by cutting a stretched transparent film into a width of 4 cm and a length of 4 cm was used in a room at 23 ° C. using a phase difference measuring device (product name “KOBRA WRXY2020” manufactured by Oji Measuring Instruments Co., Ltd.). The in-plane phase difference R548 with a wavelength of 548 nm was measured and found to be 139 nm. The results are summarized in Table 6 below.

When the polycarbonate resin film produced in Example 20 was attached as a retardation film to the screen surface layer of a display displaying a linearly polarized image, and the display was viewed through polarized sunglasses, it was not displayed in black and had a rainbow pattern. No occurrence was confirmed, and the results were good.

Although the present invention has been described in detail using specific embodiments, it will be apparent to those skilled in the art that various modifications and modifications can be made without departing from the intent and scope of the invention. This application is based on a Japanese patent application (Japanese Patent Application No. 2015-086969) filed on April 21, 2015, and the entire application is incorporated by reference.

According to the present invention, there are no problems such as deterioration of heat resistance of the film, turbidity of the film due to bleed-out substances, foreign matter of the film due to roll stains, poor appearance of the film such as gear marks, etc., and excellent appearance quality. Moreover, it is possible to provide a polycarbonate resin film having excellent uniformity in film thickness.
Therefore, it contributes to the reduction of the manufacturing process loss of the polarizing plate using this and the thinning of the structure of the image display device.

Claims (4)

With respect to 100 parts by weight of the polycarbonate resin containing a structural unit derived from the dihydroxy compound represented by the following formula (1) and 100 parts by weight of the polycarbonate resin, the melting point is 135 ° C. or higher and lower than 300 ° C. and the 5% weight loss temperature is 240. A polycarbonate resin film composed of a polycarbonate resin composition containing an ultraviolet absorber higher than ° C. in an amount of more than 0.45 parts by weight and 7 parts by weight or less , and is a compound represented by the following formula (3) in the polycarbonate resin. content is not more than 10 ppm by weight to 1200 ppm by weight, a polycarbonate resin film light transmittance at a wavelength of 380nm is 15% or less than 0.001%, and the thickness is 5 m to 120 mu m.

The polycarbonate resin film according to claim 1, wherein the ultraviolet absorber is a triazine-based, benzotriazole-based, quinolinone-based, benzoxazole-based or indole-based. A polarizer protective film using the polycarbonate resin film according to claim 1 or 2 . With respect to 100 parts by weight of the polycarbonate resin containing a structural unit derived from the dihydroxy compound represented by the following formula (1) and 100 parts by weight of the polycarbonate resin, the melting point is 135 ° C. or higher and lower than 300 ° C., and the 5% weight loss temperature is 240. An ultraviolet absorber higher than ° C. is contained in an amount of more than 0.45 parts by weight and 7 parts by weight or less, and the content of the compound represented by the following formula (3) in the polycarbonate resin is 10% by weight or more and 1200% by weight or less. A polycarbonate resin composition.