JP5906899B2 - Method for producing unstretched polycarbonate resin film - Google Patents

Description

  The present invention relates to a polycarbonate resin unstretched film and a method for producing the same.

  Polyester resins, polycarbonate resins, cyclic polyolefin resins, cellulose resins and the like are exclusively used in films used in fields that require various properties such as high transparency, high strength, and high heat resistance. These films include unstretched films and stretched films. In recent years, demands for thinning and uniform quality have increased, and in order to meet this demand, films with improved thickness accuracy have been required. It is coming.

As a specific example of a method for producing a film having particularly excellent thickness accuracy, there is a solution casting method. The solution casting method is a method in which a resin solution is continuously poured onto a smooth drum or belt, heated to remove the solvent, and wound up as a film. With this method, it is possible to obtain a film with little thermal degradation, few scratches and foreign matter defects, and extremely high thickness accuracy, but on the other hand, the solvent removal equipment is large, the production speed is slow, and the production cost is very high. There was a problem to be raised.

  On the other hand, melt extrusion methods such as the T-die method are excellent in productivity and have an advantage that the production cost is lower than that of the solution casting method.

  Moreover, if it stretches about the unstretched film obtained by any film forming method, the stretched film which is generally excellent in thickness accuracy than the original unstretched film can be obtained.

  However, in general, in the melt extrusion method, various factors in the process are entangled with each other, causing unevenness and pulsation in the discharge of the resin. Therefore, the necking shape and thickness of the resin melt-extruded from the die into a film shape easily fluctuate. Furthermore, the molten resin is likely to fluctuate due to wind or thermal convection generated between the die and the roll. For this reason, it has been difficult to sufficiently improve the thickness accuracy in both the width direction and the flow direction of the film.

However, in film applications that are required to have optical isotropy, for example, it is not possible to take a method of increasing the thickness accuracy by stretching, and to increase the thickness accuracy in the production stage of an unstretched film to the last There is a need.
In addition, for example, in a film application in which it is required to design a predetermined anisotropy optically, in order to make the orientation in-plane uniform, generally in the stage of producing an unstretched raw fabric, It is necessary to manufacture an original fabric with high thickness accuracy and add a stretching process in which this is controlled within a certain range.
As described above, in order to meet the above requirements, it is required to solve this problem even though it is difficult to manufacture a raw material with high thickness accuracy by the melt extrusion method.

Furthermore, a novel polycarbonate resin different from the conventional aromatic polycarbonate resin that satisfies all the various properties such as high transparency, high strength, high heat resistance, and high weather resistance has been proposed. Discloses a method of forming a film of such a polycarbonate resin by a solution casting method, and Patent Document 3 discloses a method of forming a film by a melt extrusion method.
However, for the unstretched film obtained by melt extrusion molding of this polycarbonate resin, the fact that the thickness accuracy is greatly improved has not been studied so far. It was not obtained.

JP 2006-028441 A International Publication No. 2006/041190 Pamphlet JP 2008-274203 A

  The present invention has been made in view of the above-described conventional situation, and it is an object of the present invention to provide an extremely stretched polycarbonate resin unstretched film obtained by melt extrusion molding a polycarbonate resin having a specific structure. .

As a result of intensive studies in view of the above problems, the present inventors have obtained a very high thickness accuracy polycarbonate resin obtained by melt extrusion molding a polycarbonate resin having a specific structure by using a specific manufacturing method. The inventors have found that an unstretched film can be produced, and have completed the present invention.
That is, the gist of the present invention is as follows.

[1] A method for producing an unstretched polycarbonate resin film by melt-extruding a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following formula (1). A gear pump is provided between the die and the resin pressure fluctuation at the outlet side of the gear pump is 0.1% or more and 2.9 % or less per 30 minutes , and a polycarbonate resin unstretched film satisfying the following condition (I) is manufactured. A method for producing an unstretched polycarbonate resin film.
Condition (I): “Maximum of film thickness measured at 50 mm intervals from one end to the other end in the width direction of the film between two points 10% inside the film width from both ends in the width direction of the film. The value of “value Tmax−minimum value Tmin” is 1.4% or less of the average value Ta, and “maximum value of the film thickness measured at intervals of 50 mm over 1 m in the flow direction at the center in the width direction of the film. The value of “tmax−minimum value tmin” is 1.4% or less of the average value ta.

[2] The polycarbonate resin unstretched film according to [1], wherein the reduced viscosity of the polycarbonate resin is 0.30 dL / g or more and 1.20 dL / g or less, and the range of the reduced viscosity is 0.05 dL / g or less. Manufacturing method.

[3] The method for producing an unstretched polycarbonate resin film according to [1] or [2], wherein the polycarbonate resin has a glass transition temperature of 90 ° C. or higher and 160 ° C. or lower.

  According to the production method of the present invention, a polycarbonate resin unstretched film having an extremely high thickness accuracy can be obtained by melt extrusion molding a polycarbonate resin having a specific structure.

  In addition, the polycarbonate resin unstretched film of the present invention is an unstretched film with extremely high thickness accuracy formed by melt extrusion molding a polycarbonate resin having a specific structure, and thus has high transparency, high strength, and high heat resistance. , High weather resistance, and thickness accuracy can be suitably used.

  DESCRIPTION OF EMBODIMENTS Embodiments of the present invention will be described in detail below. However, the description of the constituent elements described below is an example (representative example) of an embodiment of the present invention. It is not limited to the contents.

  The method for producing an unstretched polycarbonate resin film of the present invention comprises producing a polycarbonate resin unstretched film by melt extrusion molding a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following formula (1). This method is characterized in that the following condition [1] is adopted, and preferably any one or more of the following [2] to [4] is adopted.

[1] A gear pump is provided between the extruder and the T die, and the outlet side resin pressure fluctuation of the gear pump is set to 1% or more and 10% or less per 30 minutes.
[2] The distance (air gap) between the lower end of the lip of the T die and the center contact position of the cooling roll and the film is 10 mm or more and 60 mm or less.
[3] In the T die, the lip length in the flow direction of the film is set to 15 mm or more and 50 mm or less.
[4] The neck-in rate in the width direction is set to 92% or more and 98% or less.

  In this specification, the “flow direction” of the film refers to the direction (so-called MD) in which the film flows when the resin composition melted at the time of extrusion molding is extruded from a die such as a T die, and the “width” of the film The “direction” refers to a direction (so-called TD) orthogonal to the “flow direction” and substantially horizontal to the floor surface.

  The “non-stretched” in the polycarbonate resin non-stretched film of the present invention is obtained without substantially stretching the film formed by melt extrusion of the polycarbonate resin. “No” means that a film obtained by melting and extruding polycarbonate resin from a die and solidifying by cooling with a cooling roll or the like is not intentionally subjected to roll stretching or tenter stretching.

<Polycarbonate resin>
The polycarbonate resin used in the present invention is a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following formula (1). By using the polycarbonate resin, an unstretched film having high transparency, high strength, high heat resistance, high weather resistance, and extremely high thickness accuracy can be obtained when melt extrusion molding is performed.

Examples of the dihydroxy compound represented by the formula (1) include isosorbide, isomannide, and isoide which are in a stereoisomeric relationship. These may be used individually by 1 type and may be used in combination of 2 or more type.
Since these dihydroxy compounds do not have a phenolic hydroxyl group, it is usually difficult to polymerize by an interfacial method, and the polycarbonate resin according to the present invention is usually produced by a transesterification reaction using a carbonic acid diester.

  Among these dihydroxy compounds, isosorbide obtained by dehydrating and condensing sorbitol produced from various starches that are abundant as plant-derived resources, is easy to obtain and manufacture, and is light resistant. Are most preferable from the viewpoints of properties, optical properties, moldability, heat resistance and carbon neutral.

  A dihydroxy compound having a cyclic ether structure represented by the above formula (1) as typified by isosorbide is likely to be gradually oxidized by oxygen. For this reason, when storing or handling during production, it is important to prevent moisture from being mixed, to use an oxygen scavenger, or to be in a nitrogen atmosphere in order to prevent decomposition by oxygen. When isosorbide is oxidized, decomposition products such as formic acid are generated. For example, when a polycarbonate resin is produced using isosorbide containing these decomposition products, the resulting polycarbonate resin may be colored or the physical properties may be significantly deteriorated. Alternatively, the polymerization reaction is affected, and a high molecular weight polymer may not be obtained. However, when a stabilizer for preventing the generation of formic acid is added, depending on the type of the stabilizer, the resulting polycarbonate resin may be colored or the physical properties may be significantly deteriorated.

  Therefore, in the present invention, the following specific stabilizer is preferably used. As the stabilizer, it is preferable to use a stabilizer such as a reducing agent, an antacid, an antioxidant, an oxygen scavenger, a light stabilizer, a pH stabilizer, a heat stabilizer, and the like. Since it is easy, it is preferable to contain a basic stabilizer. Among these, examples of the reducing agent include sodium borohydride and lithium borohydride, and examples of the antacid include alkalis such as sodium hydroxide. However, the addition of an alkali metal salt is not preferable because an alkali metal may serve as a polymerization catalyst, and if it is excessively added, the polymerization reaction cannot be controlled.

  Basic stabilizers include group 1 or group 2 metal hydroxides, carbonates, phosphates, phosphites, hypophosphorous acid in the long-period periodic table (Nomenclature of Inorganic Chemistry IUPAC Recommendations 2005). Salts, borates, fatty acid salts, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylethylammonium hydroxide, trimethylbenzylammonium hydroxide, trimethylphenylammonium hydroxide, Triethylmethylammonium hydroxide, triethylbenzylammonium hydroxide, triethylphenylammonium hydroxide, tributylbenzylammonium hydroxide, tributylphenylammonium Basic ammonium compounds such as monium hydroxide, tetraphenylammonium hydroxide, benzyltriphenylammonium hydroxide, methyltriphenylammonium hydroxide, butyltriphenylammonium hydroxide, 4-aminopyridine, 2-aminopyridine, N, N -Dimethyl-4-aminopyridine, 4-diethylaminopyridine, 2-hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 2-dimethylaminoimidazole, 2-methoxyimidazole, imidazole, 2-mercaptoimidazole, 2-methylimidazole And amine compounds such as aminoquinoline. Of these, sodium or potassium phosphates and phosphites are preferable, and disodium hydrogen phosphate and disodium hydrogen phosphite are particularly preferable because of their effects and ease of distillation removal described later.

  The content of these basic stabilizers in the dihydroxy compound is not particularly limited. However, from the viewpoint of balancing the expression of the effect of preventing alteration of the dihydroxy compound and the suppression of the modification of the dihydroxy compound, the dihydroxy compound is usually On the other hand, it is 0.0001% by weight to 1% by weight, preferably 0.001% by weight to 0.1% by weight.

  In addition, when dihydroxy compounds containing these basic stabilizers are used as raw materials for the production of polycarbonate resin, the basic stabilizer itself becomes a polymerization catalyst, which not only makes it difficult to control the polymerization rate and quality, but also deteriorates the initial hue. The basic stabilizer may be removed by ion exchange resin or distillation before using it as a raw material for the production of polycarbonate resin. preferable.

  In addition, in order to obtain a dihydroxy compound that does not contain oxidative decomposition products generated during storage and handling during production, or to remove the aforementioned basic stabilizer, distillation purification of the dihydroxy compound may be performed. preferable. The distillation in this case may be simple distillation or continuous distillation, and is not particularly limited. As distillation conditions, it is preferable to carry out distillation under reduced pressure in an inert gas atmosphere such as argon or nitrogen. In order to suppress thermal denaturation, it is 250 ° C. or lower, preferably 200 ° C. or lower, particularly 180 °. It is preferable to carry out under the conditions of ℃ or less.

  By such distillation purification, polycarbonate resin is obtained by setting the formic acid content in the dihydroxy compound represented by the formula (1) to 20 ppm by weight or less, preferably 10 ppm by weight or less, particularly preferably 5 ppm by weight or less. A polycarbonate resin excellent in hue and thermal stability can be produced without impairing the polymerization reactivity during production. Formic acid content is measured using ion chromatography according to the following procedure. In the following procedure, isosorbide is taken as an example of a typical dihydroxy compound.

About 0.5 g of isosorbide is precisely weighed and collected in a 50 ml volumetric flask and made up to volume with pure water. A sodium formate aqueous solution is used as a standard sample, and the peak having the same retention time as that of the standard sample is defined as formic acid, and quantified by an absolute calibration curve method from the peak area.
The ion chromatograph uses DX-500 type manufactured by Dionex, and an electric conductivity detector is used as a detector. As a measurement column, AG-15 is used as a guard column manufactured by Dionex, and AS-15 is used as a separation column. A measurement sample is injected into a 100 μl sample loop, and 10 mM NaOH is used as an eluent, and the measurement is performed at a flow rate of 1.2 ml / min and a thermostat temperature of 35 ° C. A membrane suppressor is used as the suppressor, and a 12.5 mM-H 2 SO 4 aqueous solution is used as the regenerating solution.

  Since the structure derived from the dihydroxy compound represented by the formula (1) is rigid, if there are too many structures derived from the dihydroxy compound represented by the formula (1) in the polycarbonate resin, the structure tends to be hard and brittle. There is a tendency for formability or mechanical properties to decrease. On the other hand, if the amount is too small, the heat resistance of the polycarbonate resin is lowered and it may be difficult to use as a film. Therefore, in the production of the polycarbonate resin, by using other dihydroxy compounds together with the dihydroxy compound represented by the formula (1), it is possible to obtain effects such as improvement in flexibility or moldability of the polycarbonate resin. preferable.

  When a structural unit derived from another dihydroxy compound other than the structural unit derived from the dihydroxy compound represented by the above formula (1) is introduced into the polycarbonate resin for imparting flexibility or the like of the polycarbonate resin, it is used in the present invention. The polycarbonate resin preferably contains 10 mol% or more of the structural unit derived from the dihydroxy compound represented by the formula (1) with respect to all the structural units derived from the dihydroxy compound, more preferably 15 mol% or more, Particularly preferred is 20 mol% or more. Moreover, it is preferable to contain normally 95 mol% or less, More preferably, it is 90 mol% or less, Most preferably, it is 85 mol% or less.

  If the content of the structural unit derived from the dihydroxy compound represented by the formula (1) with respect to all structural units derived from the dihydroxy compound is 10 mol% or more, the heat resistance is insufficient or the film is deformed by heat. This is preferable because there is little risk of damage. On the other hand, if the content is 95 mol% or less, the water absorption rate is low, and deterioration due to heat is reduced, so that the possibility of deterioration of the color tone is small, which is preferable. Moreover, since polycarbonate resin can fully be made into high molecular weight, it is excellent in impact resistance, and since there is little possibility that a film will fracture | rupture, it is preferable.

  As structural units derived from other dihydroxy compounds other than the structural unit derived from the dihydroxy compound represented by the formula (1) introduced into the polycarbonate resin, structural units derived from aliphatic dihydroxy compounds and alicyclic compounds Examples include structural units derived from dihydroxy compounds. Specific examples of the aliphatic dihydroxy compound and the alicyclic dihydroxy compound include the following.

<Aliphatic dihydroxy compound>
Examples of the aliphatic dihydroxy compound include 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, and 2-ethyl. -1,6-hexanediol, 2,2,4-trimethyl-1,6-hexanediol, 1,10-decanediol, hydrogenated dilinoleyl glycol, hydrogenated dioleyl glycol and the like.

  In addition, the said exemplary compound is an example of the aliphatic dihydroxy compound which can be used for this invention, Comprising: It is not limited to these at all. These aliphatic dihydroxy compounds may be used individually by 1 type, and 2 or more types may be mixed and used for them.

  In the polycarbonate resin used in the present invention, the molar ratio between the structural unit derived from the dihydroxy compound represented by the formula (1) and the structural unit derived from the aliphatic dihydroxy compound can be selected at an arbitrary ratio. By adjusting the ratio, it is possible to balance rigidity and impact resistance or to design an appropriate molding processability.

<Alicyclic dihydroxy compound>
Although it does not specifically limit as an alicyclic dihydroxy compound, Usually, the compound containing a 5-membered ring structure or a 6-membered ring structure is mentioned. When the alicyclic dihydroxy compound has a 5-membered ring structure or a 6-membered ring structure, the heat resistance of the obtained polycarbonate resin tends to increase. The six-membered ring structure may be fixed in a chair shape or a boat shape by a covalent bond. Carbon number contained in an alicyclic dihydroxy compound is 70 or less normally, Preferably it is 50 or less, More preferably, it is 30 or less. An alicyclic dihydroxy compound having 70 or less carbon atoms is preferable because it is easy to synthesize and purify, and is inexpensive and easily available.

Specific examples of the alicyclic dihydroxy compound containing a 5-membered ring structure or a 6-membered ring structure include alicyclic dihydroxy compounds represented by the following general formula (I) or (II).
_{HOCH 2 -R 9 -CH 2 OH (} I)
HO—R ₁₀ —OH (II)
(However, in formula (I) and formula (II), R ₉ and R ₁₀ each independently represent a divalent group containing a substituted or unsubstituted cycloalkyl structure having 4 to 20 carbon atoms. )

As cyclohexanedimethanol which is an alicyclic dihydroxy compound represented by the above general formula (I), in general formula (I), R ₉ is the following general formula (Ia) (wherein R ₁₁ is a hydrogen atom, or Represents a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms.). Specific examples thereof include 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, and the like.

Examples of tricyclodecane dimethanol and pentacyclopentadecane dimethanol, which are alicyclic dihydroxy compounds represented by the above general formula (I), include, in general formula (I), R ₉ is represented by the following general formula (Ib) (in the formula: , N represents 0 or 1).

As decalin dimethanol or tricyclotetradecane dimethanol, which is an alicyclic dihydroxy compound represented by the general formula (I), in general formula (I), R ₉ is represented by the following general formula (Ic) (wherein m represents 0 or 1). Specific examples thereof include 2,6-decalin dimethanol, 1,5-decalin dimethanol, 2,3-decalin dimethanol, and the like.

Moreover, as norbornane dimethanol which is an alicyclic dihydroxy compound represented by the general formula (I), various isomers in which R ₉ is represented by the following general formula (Id) in the general formula (I) Include. Specific examples thereof include 2,3-norbornane dimethanol, 2,5-norbornane dimethanol and the like.

The adamantane dimethanol, which is an alicyclic dihydroxy compound represented by the general formula (I), includes various isomers in which R ₉ is represented by the following general formula (Ie) in the general formula (I). Specific examples of such a material include 1,3-adamantane dimethanol.

In addition, cyclohexanediol, which is an alicyclic dihydroxy compound represented by the general formula (II), in the general formula (II), R ₁₀ is represented by the following general formula (IIa) (wherein R ₁₁ is a hydrogen atom, substituted Or an unsubstituted alkyl group having 1 to 12 carbon atoms). Specific examples thereof include 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 2-methyl-1,4-cyclohexanediol, and the like.

As tricyclodecanediol and pentacyclopentadecanediol, which are alicyclic dihydroxy compounds represented by the general formula (II), in general formula (II), R ₁₀ is represented by the following general formula (IIb) (wherein n Represents 0 or 1).

As decalin diol or tricyclotetradecane diol, which is an alicyclic dihydroxy compound represented by the general formula (II), in general formula (II), R ₁₀ is represented by the following general formula (IIc) (where m is It represents 0 or 1). Specifically, 2,6-decalindiol, 1,5-decalindiol, 2,3-decalindiol and the like are used as such.

The norbornanediol which is an alicyclic dihydroxy compound represented by the general formula (II) includes various isomers in which R ₁₀ is represented by the following general formula (IId) in the general formula (II). Specifically, 2,3-norbornanediol, 2,5-norbornanediol, and the like are used as such.

The adamantanediol which is an alicyclic dihydroxy compound represented by the general formula (II) includes various isomers in which R ₁₀ is represented by the following general formula (IIe) in the general formula (II). Specifically, 1,3-adamantanediol etc. are used as such.

  Among the specific examples of the alicyclic dihydroxy compounds described above, cyclohexane dimethanols, tricyclodecane dimethanols, adamantane diols, and pentacyclopentadecane dimethanols are preferable, and are easily available and easy to handle. From the viewpoint, 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,2-cyclohexanedimethanol, and tricyclodecane dimethanol are particularly preferable.

  In addition, the said exemplary compound is an example of the alicyclic dihydroxy compound which can be used for this invention, Comprising: It is not limited to these at all. These alicyclic dihydroxy compounds may be used individually by 1 type, and 2 or more types may be mixed and used for them.

  In the polycarbonate resin used in the present invention, the molar ratio between the structural unit derived from the dihydroxy compound represented by the formula (1) and the structural unit derived from the alicyclic dihydroxy compound can be selected at any ratio. By adjusting the molar ratio, impact strength (for example, notched Charpy impact strength) may be improved, and a desired glass transition temperature of the polycarbonate resin can be obtained.

  In the polycarbonate resin used in the present invention, the molar ratio between the structural unit derived from the dihydroxy compound represented by the formula (1) and the structural unit derived from the alicyclic dihydroxy compound can be selected at any ratio. By adjusting the molar ratio, impact strength (for example, notched Charpy impact strength) may be improved, and a desired glass transition temperature of the polycarbonate resin can be obtained.

  In the polycarbonate resin used in the present invention, the molar ratio between the structural unit derived from the dihydroxy compound represented by the formula (1) and the structural unit derived from the alicyclic dihydroxy compound is 95: 5 to 30:70. It is preferably 80:20 to 40:60, and more preferably. When the molar ratio is within the above range, the polycarbonate resin used in the present invention is less likely to be colored due to heat retention, and can have high molecular weight, improved impact strength, and improved heat resistance by maintaining the glass transition temperature. This is preferable.

  In the polycarbonate resin used in the present invention, in addition to the structural unit derived from the dihydroxy compound represented by the formula (1), the structural unit derived from the aliphatic dihydroxy compound, the structural unit derived from the alicyclic dihydroxy compound, Furthermore, structural units derived from other dihydroxy compounds may be included. Examples of other dihydroxy compounds include dihydroxy compounds having a site represented by the following general formula (2) in a part of the structure other than the dihydroxy compounds represented by the formula (1), aromatic dihydroxy compounds, and the like. Can be mentioned.

(However, the site represented by the above general formula (2) unless a part of _-CH 2 -O-H.)

  Specific examples of the dihydroxy compound having a portion represented by the general formula (2) in a part of the structure other than the dihydroxy compound represented by the formula (1) include diethylene glycol, triethylene glycol, and tetraethylene. Oxyalkylene glycols such as glycol, 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- Droxyethoxy) -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, and dihydroxy compounds having an aromatic group in the side chain and an ether group bonded to the aromatic group in the main chain being the moiety represented by the general formula (2). It is done. Moreover, the dihydroxy compound whose part of heterocyclic groups, such as a compound which has cyclic ether structures, such as spiroglycol represented by following General formula (3), is a site | part represented by the said General formula (2) is mentioned.

(In the general formula (3), R _{1 to} R ₄ are each independently an alkyl group having 1 to 3 carbon atoms.)

  Examples of the dihydroxy compound represented by the general formula (3) include 3,9-bis (1,1-dimethyl-2-hydroxyethyl) -2,4,8,10-tetraoxaspiro (5.5) undecane. (Common name: spiroglycol), 3,9-bis (1,1-diethyl-2-hydroxyethyl) -2,4,8,10-tetraoxaspiro (5.5) undecane, 3,9-bis ( 1,1-dipropyl-2-hydroxyethyl) -2,4,8,10-tetraoxaspiro (5.5) undecane, dioxane glycol represented by the following formula (4), and the like.

  Examples of the aromatic dihydroxy compound include bisphenol compounds (including substituted and unsubstituted). Specifically, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 1 , 1-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) butane 1,1-bis (4-hydroxyphenyl) pentane, 2,2-bis (4-hydroxyphenyl) pentane, 3,3-bis (4-hydroxyphenyl) pentane, 2,2-bis (4-hydroxyphenyl) ) -3-Methylbutane, 1,1-bis (4-hydroxyphenyl) hexane, 2,2-bis (4-hydroxyphenyl) hex 3,3-bis (4-hydroxyphenyl) hexane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1- Bisphenol compounds having no substituent on the aromatic ring such as bis (4-hydroxyphenyl) cyclohexane; bis (3-phenyl-4-hydroxyphenyl) methane, 1,1-bis (3-phenyl-4-hydroxyphenyl) ) Having an aryl group as a substituent on an aromatic ring such as ethane, 1,1-bis (3-phenyl-4-hydroxyphenyl) propane, 2,2-bis (3-phenyl-4-hydroxyphenyl) propane Bisphenol compounds; bis (4-hydroxy-3-methylphenyl) methane, 1,1-bis (4-hydroxy-3-methyl) Enyl) ethane, 1,1-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3-) Methylphenyl) cyclohexane, bis (4-hydroxy-3-ethylphenyl) methane, 1,1-bis (4-hydroxy-3-ethylphenyl) ethane, 1,1-bis (4-hydroxy-3-ethylphenyl) Propane, 2,2-bis (4-hydroxy-3-ethylphenyl) propane, 1,1-bis (4-hydroxy-3-ethylphenyl) cyclohexane, 2,2-bis (4-hydroxy-3-isopropylphenyl) ) Propane, 2,2-bis (4-hydroxy-3- (sec-butyl) phenyl) propane, bis (4-hydroxy-3,5-di) Methylphenyl) methane, 1,1-bis (4-hydroxy-3,5-dimethylphenyl) ethane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 1,1-bis (4 -Hydroxy-3,5-dimethylphenyl) cyclohexane, bis (4-hydroxy-3,6-dimethylphenyl) methane, 1,1-bis (4-hydroxy-3,6-dimethylphenyl) ethane, 2,2- Bis (4-hydroxy-3,6-dimethylphenyl) propane, bis (4-hydroxy-2,3,5-trimethylphenyl) methane, 1,1-bis (4-hydroxy-2,3,5-trimethylphenyl) ) Ethane, 2,2-bis (4-hydroxy-2,3,5-trimethylphenyl) propane, bis (4-hydroxy-2,3,5-trimethylpheny) ) Aromatics such as phenylmethane, 1,1-bis (4-hydroxy-2,3,5-trimethylphenyl) phenylethane, 1,1-bis (4-hydroxy-2,3,5-trimethylphenyl) cyclohexane Bisphenol compounds having an alkyl group as a substituent on the ring; bis (4-hydroxyphenyl) phenylmethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,1-bis (4-hydroxyphenyl) ) A bisphenol compound in which a divalent group connecting aromatic rings such as -1-phenylpropane, bis (4-hydroxyphenyl) diphenylmethane, bis (4-hydroxyphenyl) dibenzylmethane has an aryl group as a substituent; 4′-dihydroxydiphenyl ether, 3,3 ′, 5,5′-tetramethyl-4, Bisphenol compounds in which aromatic rings such as '-dihydroxydiphenyl ether are linked by an ether bond; 4,4'-dihydroxydiphenylsulfone, 3,3', 5,5'-tetramethyl-4,4'-dihydroxydiphenylsulfone, etc. Bisphenol compounds in which aromatic rings are linked by sulfone bonds; sulfide bonds for aromatic rings such as 4,4'-dihydroxydiphenyl sulfide and 3,3 ', 5,5'-tetramethyl-4,4'-dihydroxydiphenyl sulfide The bisphenol compound etc. which couple | bonded together are mentioned, Preferably, 2, 2-bis (4-hydroxyphenyl) propane (other name: bisphenol-A) is mentioned.

  However, if the polycarbonate resin contains a large amount of structural units derived from the aromatic dihydroxy compound, yellowing may occur due to ultraviolet absorption when used outdoors. For this reason, when it is necessary to prevent this, the content of the structural unit derived from the aromatic dihydroxy compound is 0 mol% or more and less than 40 mol% with respect to the structural unit derived from all dihydroxy compounds in the polycarbonate resin. 0 mol% or more and less than 30 mol% is more preferred, 0 mol% or more and less than 20 mol% is even more preferred, 0 mol% or more and less than 10 mol% is particularly preferred, and 0 mol% or more and less than 5 mol% is most preferred.

  On the other hand, in applications where there is no risk of exposure to ultraviolet light, improvements in heat resistance, surface impact resistance, molding processability, and the like can be expected by including a structural unit derived from the aromatic dihydroxy compound.

In general, the dihydroxy compound represented by the above formula (1) has an equilibrium constant in the polymerization reaction that is inclined toward the progress of polymerization as compared with aromatic dihydroxy compounds such as bisphenol-A. Otherwise, the polymerization reaction tends to be rapid and the reaction control tends to be difficult.
For this reason, if a small amount of the aromatic dihydroxy compound is added at the final stage of the polymerization reaction, the polymerization reaction is rapidly accelerated even when heated or phenol devolatilized by closing the polymerization end with the aromatic dihydroxy compound. You can also expect the effect of not having to.

  The above-mentioned other dihydroxy compounds may be used alone or in combination of two or more.

<Carbonated diester>
The polycarbonate resin used in the present invention can be obtained by polycondensation by a transesterification reaction using a dihydroxy compound containing the dihydroxy compound represented by the above formula (1) and a carbonic acid diester as raw materials.

  As a carbonic acid diester used, what is normally represented by following General formula (5) is mentioned. These carbonic acid diesters may be used alone or in combination of two or more.

However, in the above general formula (5), A ¹ and A ² are each independently a substituted or unsubstituted aliphatic group having 1 to 18 carbon atoms or a substituted or unsubstituted aromatic group. .

  Examples of the carbonic acid diester represented by the general formula (5) include diaryl carbonates such as diphenyl carbonate and ditolyl carbonate, and dialkyl carbonates such as dimethyl carbonate, diethyl carbonate, and di-t-butyl carbonate. Preferred are diaryl carbonates such as diphenyl carbonate and diphenyl carbonate having a substituent, and among diaryl carbonates, diphenyl carbonate is preferred.

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

<Transesterification reaction catalyst>
The polycarbonate resin used in the present invention is obtained by transesterifying the dihydroxy compound containing the dihydroxy compound represented by the formula (1) and the carbonic acid diester as described above. More specifically, it can be obtained by transesterification and removing by-product monohydroxy compounds and the like out of the system. In this case, polycondensation is usually carried out by transesterification in the presence of a transesterification catalyst.

  The transesterification reaction catalyst (hereinafter sometimes simply referred to as “catalyst” or “polymerization catalyst”) that can be used in the production of the polycarbonate resin used in the present invention is, in particular, a light transmittance or a yellow index (YI) value at a wavelength of 350 nm. May be affected.

  The catalyst to be used is preferably one that can satisfy the light resistance of the obtained polycarbonate resin, that is, a YI value that will be described later can be set to a predetermined value or less, such as Group 1 or Group 2 (hereinafter referred to as “Long Periodic Periodic Table”). And basic compounds such as metal compounds, basic boron compounds, basic phosphorus compounds, basic ammonium compounds, amine compounds, and the like. Among these, Preferably a group 1 metal compound and / or a group 2 metal compound are used.

  It is possible to use a basic compound such as a basic boron compound, a basic phosphorus compound, a basic ammonium compound, and an amine compound together with the Group 1 metal compound and / or the Group 2 metal compound. It is particularly preferred to use only Group 1 metal compounds and / or Group 2 metal compounds.

  In addition, the group 1 metal compound and / or the group 2 metal compound is usually used in the form of a hydroxide or a salt such as a carbonate, a carboxylate, or a phenol salt. From the viewpoint of easiness, a hydroxide, carbonate, and acetate are preferable, and acetate is preferable from the viewpoint of hue and polymerization activity.

  Examples of the Group 1 metal compound include sodium hydroxide, sodium hydrogen carbonate, sodium carbonate, sodium acetate, sodium stearate, sodium borohydride, sodium phenyl borohydride, sodium benzoate, disodium hydrogen phosphate, phenyl phosphoric acid. Sodium compounds such as disodium, sodium alcoholate or phenolate, and disodium salt of bisphenol A, potassium hydroxide, potassium bicarbonate, potassium carbonate, potassium acetate, potassium stearate, potassium borohydride, potassium borohydride Potassium compounds such as potassium benzoate, dipotassium hydrogen phosphate, dipotassium phenyl phosphate, potassium alcoholate or phenolate, and dipotassium salt of bisphenol A, lithium hydroxide, Lithium oxyhydrogen, lithium carbonate, lithium acetate, lithium stearate, lithium borohydride, lithium phenyl borohydride, lithium benzoate, 2 lithium hydrogen phosphate, 2 lithium phenyl phosphate, lithium alcoholate or phenolate, and bisphenol A lithium compound such as dilithium salt of A, and cesium hydroxide, cesium bicarbonate, cesium carbonate, cesium acetate, cesium stearate, cesium borohydride, cesium phenyl borohydride, cesium benzoate, 2 cesium hydrogen phosphate, phenyl Examples include cesium compounds such as 2 cesium phosphate, alcoholate or phenolate of cesium, and 2 cesium salt of bisphenol A. Of these, lithium compounds are preferred.

  Examples of the Group 2 metal compound include calcium compounds such as calcium hydroxide, calcium bicarbonate, calcium carbonate, calcium acetate and calcium stearate, and barium such as barium hydroxide, barium bicarbonate, barium carbonate, barium acetate and barium stearate. Compounds, magnesium compounds such as magnesium hydroxide, magnesium hydrogen carbonate, magnesium carbonate, magnesium acetate and magnesium stearate, and strontium compounds such as strontium hydroxide, strontium hydrogen carbonate, strontium carbonate, strontium acetate and strontium stearate, etc. . Among these, a magnesium compound, a calcium compound, and a barium compound are preferable, and at least one metal compound selected from the group consisting of a magnesium compound and a calcium compound is more preferable from the viewpoint of polymerization activity and the hue of the obtained polycarbonate resin, and most preferably calcium. A compound.

  Examples of the basic boron compound include tetramethyl boron, tetraethyl boron, tetrapropyl boron, tetrabutyl boron, trimethylethyl boron, trimethylbenzyl boron, trimethylphenyl boron, triethylmethyl boron, triethylbenzyl boron, triethylphenyl boron, tributylbenzyl. Examples include sodium salts such as boron, tributylphenyl boron, tetraphenyl boron, benzyltriphenyl boron, methyltriphenyl boron, and butyltriphenyl boron, potassium salts, lithium salts, calcium salts, barium salts, magnesium salts, and strontium salts. .

  Examples of basic phosphorus compounds 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, trimethylphenylammonium hydroxide, Triethylmethylammonium hydroxide, triethylbenzylammonium hydroxide, triethylphenylammonium hydroxide, tributylbenzylammonium hydroxide, tributylphenylammonium hydroxide, tetraphenylammonium hydroxide, benzyltriphenylammonium hydroxide, methyltriphenylammonium hydroxide Sid and butyl triphenyl ammonium hydroxide, and the like.

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

  The amount of the polymerization catalyst used is preferably 0.1 to 300 μmol, more preferably 0.5 to 100 μmol, per 1 mol of all dihydroxy compounds used. In particular, when using at least one metal compound selected from the group consisting of lithium and a metal of Group 2 of the long-period periodic table, in particular, at least one metal compound selected from the group consisting of a magnesium compound and a calcium compound is used. In this case, the amount of metal is preferably 0.1 to 20 μmol, more preferably 0.5 to 10 μmol, and particularly preferably 0.7 to 3 μmol, per 1 mol of all dihydroxy compounds used.

  When the amount of the polymerization catalyst used is 0.1 μmol or more, the polymerization rate becomes a certain level or more, so that it is not necessary to increase the polymerization temperature when trying to obtain a polycarbonate resin having a desired molecular weight. The hue or light resistance of the resin deteriorates, the unreacted raw material volatilizes during the polymerization, and the molar ratio of the dihydroxy compound containing the dihydroxy compound represented by the formula (1) and the carbonic acid diester changes, and the desired molecular weight Since there is little possibility that it will not reach, it is preferable. On the other hand, if the amount of the polymerization catalyst used is 300 μmol or less, the hue of the obtained polycarbonate resin and the light resistance of the polycarbonate resin are less likely to deteriorate, which is preferable. Further, it is preferable because the possibility of reaching the target molecular weight without sufficiently reducing the pressure in the polymerization reactor and the possibility that the remaining monomer is not sufficiently devolatilized are small.

  In addition, when a group 1 metal, especially lithium, sodium, potassium, and cesium are contained in a large amount in the polycarbonate resin, the hue may be adversely affected, and the metal is not only from the catalyst used but also from the raw material or the reactor. In general, the total amount of these compounds in the polycarbonate resin is preferably 1 ppm by weight or less, more preferably 0.8 ppm by weight or less, and still more preferably 0.8 ppm as a metal amount. 7 ppm by weight or less.

  The amount of metal in the polycarbonate resin can be measured using a method such as atomic emission, atomic absorption, or Inductively Coupled Plasma (ICP) after recovering the metal in the polycarbonate resin by a method such as wet ashing.

<Production method of polycarbonate resin>
The polycarbonate resin used in the present invention is a polycondensation of a dihydroxy compound containing a dihydroxy compound represented by the formula (1) and a carbonic acid diester represented by the general formula (5) by an ester exchange reaction in the presence of a catalyst. Can be obtained.
At this time, the raw material dihydroxy compound and carbonic acid diester may be mixed uniformly before the transesterification reaction, or may be added simultaneously to the polymerization tank without mixing, but they are preferably mixed uniformly.

  The mixing temperature is usually preferably 80 ° C. or higher, more preferably 90 ° C. or higher, and the upper limit is usually preferably 250 ° C. or lower, more preferably 200 ° C. or lower, still more preferably 150 ° C. or lower. is there. Among these, 100 ° C. or higher and 120 ° C. or lower is preferable. A mixing temperature of 80 ° C. or higher is preferable because the dissolution rate is increased, and there is little risk of operating problems such as solidification due to insufficient solubility. Moreover, if the temperature of mixing is 250 degrees C or less, there exists little possibility that the thermal deterioration of a dihydroxy compound will arise, and since the hue and light resistance of the polycarbonate resin obtained become favorable, it is preferable.

  The operation of mixing the dihydroxy compound containing the dihydroxy compound represented by the above formula (1) and the carbonic acid diester represented by the above general formula (5), which is a raw material of the polycarbonate resin used in the present invention, preferably has an oxygen concentration. 10 volume% or less, more preferably 0.0001 volume% to 10 volume%, still more preferably 0.0001 volume% to 5 volume%, particularly preferably 0.0001 volume% to 1 volume%. Is preferable from the viewpoint of preventing hue deterioration.

  In order to obtain the polycarbonate resin used in the present invention, the carbonic acid diester represented by the general formula (5) should be used in a molar ratio of 0.900 to 1.200 with respect to all dihydroxy compounds used in the reaction. The molar ratio is preferably 0.995 to 0.999 or 1.001 to 1.115.

If the molar ratio is 0.900 or more, it is possible to suppress an increase in the terminal hydroxyl group of the produced polycarbonate resin, and it is possible to deteriorate the thermal stability of the polymer, color during molding, and decrease in the rate of transesterification. This is preferable because the desired high molecular weight polycarbonate resin can be obtained.
Moreover, it is preferable that the molar ratio is 1.200 or less because the possibility of a decrease in the rate of transesterification reaction is small and a desired high molecular weight polycarbonate resin can be obtained. The decrease in the transesterification reaction rate increases the heat history during the polymerization reaction, and may result in deterioration of the hue or light resistance of the resulting polycarbonate resin.

  Furthermore, if the molar ratio of the carbonic acid diester to the total dihydroxy compound used is 1.200 or less, the amount of residual carbonic acid diester in the resulting polycarbonate resin does not increase, and these absorb ultraviolet rays and thus the light resistance of the polycarbonate resin. This is preferable because it is less likely to cause deterioration of the odor, cause odor during molding, or increase the amount of deposits on the mold.

  Further, if the molar ratio of the carbonic acid diester to the total dihydroxy compound used is 0.999 or less, or 1.001 or more, the polymerization rate does not become too fast and remains in the final polymerization tank until the polymerization is completed. This is particularly preferable because the monomer can be sufficiently degassed, and there is little possibility of generation of a strange odor at the time of molding due to an increase in residual monomer in the resin, generation of bubbles due to gas generation, pulsation in a molding machine, and the like.

Further, when the raw material mixture is continuously fed to the polymerization tank by continuous polymerization, the fluctuation range of the molar ratio of the carbonic diester to the dihydroxy compound is usually preferably 0.07 or less, more preferably 0.05 or less, still more preferably 0. 0.03 or less.
If the fluctuation range is 0.07 or less, the molecular weight obtained is not too wide because uniform polymerization proceeds, and a uniform and good moldability polycarbonate resin is obtained. As a result, a uniform molded body Is preferable.

  In order to maintain high light resistance, the concentration of the carbonic acid diester represented by the general formula (5) remaining in the polycarbonate resin used in the present invention is preferably 200 ppm by weight or less, more preferably 100 ppm by weight. Hereinafter, it is more preferably 60 ppm by weight or less, particularly preferably 30 ppm by weight or less. Actually, the polycarbonate resin may contain an unreacted carbonic acid diester, and the lower limit value of the carbonic acid diester content is usually 1 ppm by weight.

  In the present invention, the method of polycondensing a dihydroxy compound and a carbonic acid diester is usually carried out in multiple stages using a plurality of reactors in the presence of the above-mentioned catalyst. The type of reaction may be any of a batch method, a continuous method, or a combination of a batch method and a continuous method.

  In the initial stage of polymerization, it is preferable to obtain a prepolymer at a relatively low temperature and low vacuum, and in the latter stage of polymerization, it is preferable to increase the molecular weight to a predetermined value at a relatively high temperature and high vacuum, but the jacket temperature at each molecular weight stage. It is important from the viewpoint of hue or light resistance to appropriately select the internal temperature and pressure in the reaction system.

  For example, if either the temperature or the pressure is changed too quickly before the polymerization reaction reaches a predetermined value, the unreacted monomer is distilled off, and the molar ratio of the dihydroxy compound and the carbonic acid diester is disturbed. There is a possibility that a polymer having a predetermined molecular weight or a terminal group cannot be obtained. Furthermore, there is a possibility that a polymer with a uniform molecular weight cannot be obtained, and when two or more dihydroxy compounds are copolymerized, there is a possibility that the composition ratio of the dihydroxy compounds may not be as prepared, and there is a polymer with a uniform composition ratio. It may not be obtained, and as a result, the formability and physical properties of the obtained film may be lowered, and the object of the present invention may not be achieved.

  Furthermore, it is effective to use a reflux condenser in the polymerization reactor in order to make the dihydroxy compound composition of the polymer uniform and to keep the molecular weight of the resulting polymer constant. The effect is great with the vessel. The temperature of the refrigerant introduced into the reflux condenser can be appropriately selected according to the monomer used.

  Usually, the temperature of the refrigerant introduced into the reflux cooler is preferably 45 to 180 ° C at the inlet of the reflux cooler, more preferably 80 to 150 ° C, and particularly preferably 100 to 150 ° C. If the temperature of the refrigerant is too high, the amount of reflux decreases and the effect is reduced. On the other hand, if the temperature is too low, the distillation efficiency of the monohydroxy compound that should be distilled off tends to decrease. Examples of the refrigerant include hot water, steam, and heat medium oil, and steam and heat medium oil are preferable.

  In order to maintain the polymerization rate appropriately and suppress the distillation of the monomer, while keeping the hue, thermal stability or light resistance of the final polycarbonate resin, etc. Selection is important.

  The polycarbonate resin used in the present invention is preferably produced by polymerizing in a plurality of stages using a plurality of reactors using a catalyst, but the reason for carrying out the polymerization in a plurality of reactors is the initial stage of the polymerization reaction. In order to shift the equilibrium to the polymerization side in the later stage of the polymerization reaction, it is important to suppress the volatilization of the monomer while maintaining the necessary polymerization rate because there are many monomers contained in the reaction solution. This is because it is important to sufficiently distill off the by-produced monohydroxy compound. Thus, in order to set different polymerization reaction conditions, it is preferable from the viewpoint of production efficiency to use a plurality of polymerization reactors arranged in series.

  The number of reactors used in the method of the present invention may be at least two as described above, but from the viewpoint of production efficiency, it is preferably three or more, more preferably 3-5. Particularly preferably four.

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

  If the temperature of the polymerization reaction is too low, the productivity is lowered or the thermal history of the product is increased. If the temperature is too high, not only the monomer is volatilized but also decomposition or coloring of the polycarbonate resin may be promoted.

  Specifically, the first stage reaction is preferably performed at 130 to 270 ° C., more preferably 150 to 240 ° C., and still more preferably 180 to 230 ° C. as the maximum internal temperature of the polymerization reactor. Preferably generated at a pressure of 110 to 1 kPa, more preferably 70 to 5 kPa, even more preferably 30 to 10 kPa (absolute pressure), preferably 0.1 to 10 hours, more preferably 0.5 to 3 hours. The reaction is carried out while distilling the hydroxy compound out of the reaction system. In a continuous polymerization facility, a polymer having a uniform molecular weight can be obtained with a uniform composition ratio by making the temperature, pressure and time as constant as possible.

  In the reaction after the second stage, the pressure of the reaction system is gradually lowered from the pressure of the first stage, and subsequently the monohydroxy compound generated is removed from the reaction system, and finally the pressure of the reaction system (absolute pressure) ) Is preferably 1 kPa or less, and the maximum internal temperature is preferably 200 ° C. to 270 ° C., more preferably 220 ° C. to 260 ° C., preferably 0.1 to 10 hours, more preferably 1 to 6 hours. Particularly preferably, it is carried out for 0.5 to 3 hours. In a continuous polymerization facility, a polymer having a uniform molecular weight can be obtained with a uniform composition ratio by making the temperature, pressure and time as constant as possible.

  In particular, in order to suppress the coloration or thermal deterioration of the polycarbonate resin and obtain a polycarbonate resin having a good hue or light resistance, the maximum internal temperature in all reaction steps is preferably less than 260 ° C, particularly 220 to 240 ° C. It is preferable that In order to suppress the decrease in the polymerization rate in the latter half of the polymerization reaction and minimize degradation due to thermal history, it is necessary to use a horizontal reactor with excellent plug flow and interface renewability at the final stage of polymerization. preferable.

  In order to obtain a polycarbonate resin having a predetermined molecular weight, if the polymerization temperature is increased and the polymerization time is too long, the ultraviolet transmittance decreases and the YI value tends to increase.

  In order to obtain a polycarbonate resin within the specified molecular weight range, the pressure and temperature are controlled to make the final polymerization tank agitation constant, the agitation current value and the agitation torque are constant, or the current value of the gear pump after the polymerization tank is constant. It is desirable to make it.

  From the viewpoint of effective utilization of resources, the by-produced monohydroxy compound is preferably reused as a raw material for diphenyl carbonate, bisphenol A, etc. after purification as necessary.

  The polycarbonate resin used in the present invention is usually cooled and solidified after polycondensation as described above, and pelletized with a rotary cutter or the like.

  The method of pelletization is not limited, but, for example, a method of extracting from a final polymerization reactor in a molten state, cooling and solidifying in the form of a strand to pelletize, or uniaxially in a molten state from the final polymerization reactor or The resin is supplied to a twin-screw extruder, melt-extruded, and 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 a strand, and once pelletized. Later, after the resin is again supplied to the single-screw or twin-screw extruder, melt-extruded, and then cooled and solidified, pelletized.

  At that time, in the extruder, the residual monomer is devolatilized under reduced pressure, or a commonly known heat stabilizer, neutralizer, ultraviolet absorber, mold release agent, colorant, antistatic agent, lubricant, lubricant. Further, a plasticizer, a compatibilizing agent, a flame retardant or the like can be added and kneaded.

  Although the melt kneading temperature in the extruder depends on the glass transition temperature or molecular weight of the polycarbonate resin, it is usually preferably 150 to 300 ° C, more preferably 200 to 270 ° C, still more preferably 230 to 260 ° C. is there. By setting the melt kneading temperature to 150 ° C. or higher, the melt viscosity of the polycarbonate resin is lowered, the load on the extruder is reduced, and the productivity is improved. Further, by setting the melt-kneading temperature to 300 ° C. or lower, it is possible to suppress thermal deterioration of the polycarbonate resin, and to prevent a decrease in mechanical strength due to a decrease in molecular weight, coloring or gas generation.

In the extruder, the vent pressure when devolatilizing under reduced pressure is usually preferably 5 kPa to 0.001 kPa, more preferably 3 kPa to 0.005 kPa, and even more preferably 2 kPa to 0.007 kPa.
If the vent pressure is in the above range, it is possible to sufficiently devolatilize the remaining monomer and generated gas, and when extruding into a strand, the strand breaks or the polymerization reaction or decomposition of the polycarbonate resin in the extruder. This is preferable because there is little risk of progress.
A uniform resin can be obtained by making the amount of resin charged into the extruder, the rotational speed of the extruder, the barrel temperature, and the vent pressure as constant as possible.
In addition, by keeping the vent and the pipe after the vent at 40 ° C. or higher, the monomer to be distilled does not solidify in the vent or the pipe after the vent, and a uniform vent pressure can be maintained.

  When the polycarbonate resin used in the present invention is produced, it is preferable to install a filter in order to prevent foreign matter from entering. The filter installation position is preferably on the downstream side of the extruder, and the foreign matter removal size (opening) of the filter is preferably 100 μm or less as the filtration accuracy for 99% removal. In particular, in the case of use that dislikes the entry of minute foreign matter, the thickness is preferably 40 μm or less, and more preferably 10 μm or less.

  Extrusion of the polycarbonate resin used in the present invention is preferably carried out in a clean room having a higher degree of cleanliness than Class 6, more preferably Class 6 as defined in JIS B9920 (2002) in order to prevent foreign matter from being mixed after extrusion. It is preferable to do.

Further, when cooling the extruded polycarbonate resin into chips, it is preferable to use a cooling method such as air cooling or water cooling. The air used for air cooling is preferably air from which foreign substances in the air have been removed in advance with a hepa filter or the like to prevent reattachment of foreign substances in the air.
When using water cooling, it is preferable to use water from which metal in water has been removed with an ion exchange resin or the like, and further, foreign matter in water has been removed with a filter. The opening of the filter to be used is preferably 10 to 0.45 μm as 99% removal filtration accuracy.

  Furthermore, it becomes a polycarbonate resin pellet with good moldability by making the shape of the obtained pellet constant.

<Physical properties of polycarbonate resin>
The molecular weight of the polycarbonate resin used in the present invention can be expressed by a reduced viscosity, and the reduced viscosity of the polycarbonate resin used in the present invention is usually preferably 0.30 dL / g or more, more preferably 0.35 dL / g or more. The upper limit of the viscosity is preferably 1.20 dL / g or less, more preferably 1.00 dL / g or less, and still more preferably 0.80 dL / g or less.

  If the reduced viscosity of the polycarbonate resin used in the present invention is too low, the mechanical strength of the obtained polycarbonate resin unstretched film may be small, and if it is too large, the fluidity at the time of molding is lowered, and the productivity or moldability is reduced. There is a tendency to lower.

The polycarbonate resin used in the present invention preferably has a small range of reduced viscosity. The range of the reduced viscosity is usually preferably 0.05 dL / g or less, more preferably 0.04 dL / g or less. If the range width of the reduced viscosity is 0.05 dL / g or less, it is preferable because the pulsation during extrusion molding and the thickness fluctuation and width fluctuation of the polycarbonate resin unstretched film of the present invention are less likely to occur.
In the present invention, the range of the reduced viscosity of the polycarbonate resin is calculated as the difference between the maximum value and the minimum value of the reduced viscosity when the polycarbonate resin is arbitrarily collected and measured during the production of the polycarbonate resin.

  Further, the lower limit of the concentration of the terminal group represented by the following general formula (6) of the polycarbonate resin used in the present invention (referred to as “terminal phenyl group concentration”) is usually preferably 20 μeq / g, more preferably 40 μeq. / G, particularly preferably 50 μeq / g, and the upper limit is usually preferably 160 μeq / g, more preferably 140 μeq / g, particularly preferably 100 μeq / g.

  If the concentration of the terminal group represented by the following general formula (6) of the polycarbonate resin used in the present invention is 160 μeq / g or less, the hue immediately after polymerization or at the time of molding and the hue after exposure to ultraviolet rays are preferable. . Moreover, if it is 20 microeq / g or more, since it has sufficient thermal stability, it is preferable.

  In order to control the concentration of the terminal group represented by the following general formula (6), in addition to controlling the molar ratio of the dihydroxy compound containing the dihydroxy compound represented by the formula (1) and the carbonic acid diester as a raw material, an ester Examples include a method for controlling the type or amount of the catalyst during the exchange reaction, the polymerization pressure, or the polymerization temperature.

  When the polycarbonate resin used in the present invention is produced using a substituted diphenyl carbonate such as diphenyl carbonate and ditolyl carbonate as the carbonic acid diester represented by the general formula (5), phenol and substituted phenol are by-produced, Although it is unavoidable that it remains in the polycarbonate resin, phenol and substituted phenol also have an aromatic ring, which absorbs ultraviolet rays and may cause deterioration of light resistance, as well as causing odor during molding. There is a case.

  The polycarbonate resin contains an aromatic monohydroxy compound having an aromatic ring such as by-product phenol of 2000 ppm by weight or more after a normal batch reaction, but the light resistance or odor reduction viewpoint, or at the time of extrusion molding From the viewpoint of suppressing pulsation, the content of the aromatic monohydroxy compound in the polycarbonate resin used in the present invention is preferably 1500 ppm by weight, using a horizontal reactor excellent in devolatilization performance or an extruder with a vacuum vent. In the following, it is more preferably 1000 ppm by weight or less, particularly 700 ppm by weight or less. However, it is difficult to completely remove the aromatic monohydroxy compound industrially, and the lower limit of the content of the aromatic monohydroxy compound in the polycarbonate resin used in the present invention is usually 1 ppm by weight.

  These aromatic monohydroxy compounds may naturally have a substituent depending on the raw material used, and may have, for example, an alkyl group having 5 or less carbon atoms.

In addition, when the number of hydrogen atoms bonded to the aromatic ring of the polycarbonate resin used in the present invention is (X) and the number of hydrogen atoms bonded to other than the aromatic ring is (Y), the hydrogen atom bonded to the aromatic ring The ratio of the number of moles to the number of moles of all hydrogen atoms is represented by X / (X + Y). However, as described above, there is a possibility that an aromatic ring having an ultraviolet absorbing ability affects the light resistance. Therefore, X / (X + Y) is preferably 0.1 or less, more preferably 0.05 or less, still more preferably 0.02 or less, and particularly preferably 0.01 or less. X / (X + Y) can be quantified by ¹ H-NMR.

Further, the glass transition temperature (Tg) of the polycarbonate resin used in the present invention is preferably 160 ° C. or lower. A glass transition temperature of 160 ° C. or lower is preferable because it is less likely to be colored or embrittled due to thermal deterioration during extrusion molding. Moreover, since the dihydroxy compound represented by the formula (1) generally tends to be thermally decomposed even under an inert atmosphere, it is preferable that the temperature of the molten resin need not be set too high, since there is little possibility of causing significant thermal decomposition.
The glass transition temperature of the polycarbonate resin used in the present invention is more preferably 150 ° C. or less, further preferably 145 ° C. or less, and particularly preferably 143 ° C. or less.
The glass transition temperature of the polycarbonate resin used in the present invention is usually 90 ° C. or higher, preferably 95 ° C. or higher, more preferably 100 ° C. or higher, and particularly preferably 110 ° C. or higher.

As a method for lowering the glass transition temperature of the polycarbonate resin and achieving a temperature of 160 ° C. or lower, the ratio of the structural unit derived from the dihydroxy compound represented by the formula (1) is reduced, or a fat having low heat resistance Examples include a method of selecting a cyclic dihydroxy compound or reducing the proportion of structural units derived from an aromatic dihydroxy compound such as a bisphenol compound.
The glass transition temperature is measured by heating at a rate of temperature increase of 10 ° C./min using a differential scanning calorimeter (DSI220, manufactured by SII Nano Technology) in accordance with JIS-K7121. Refers to the onset temperature of the outer glass transition.

Further, the melt viscosity of the polycarbonate resin used in the present invention is measured using a capillograph, and is preferably 1500 Pa · s or more and 3500 Pa · s or less at a measurement temperature of 240 ° C. and a shear rate of 91.2 sec ⁻¹ , and 2000 Pa · More preferably, it is s or more and 3000 Pa · s or less.
In view of the mechanical properties and color tone of the polycarbonate resin, or the flowability during melt polymerization or molding, the melt viscosity is preferably within the above range. If the melt viscosity is 3500 Pa · s or less, the mechanical properties are improved, and it is not necessary to increase the processing temperature. Therefore, it is possible to suppress coloring and thermal decomposition of the resin, which is preferable.

[Phosphoric acid compound / phosphorous acid compound]
When a polycarbonate resin is produced by a melt polymerization method, one or more of a phosphoric acid compound and a phosphorous acid compound can be added during polymerization for the purpose of preventing coloring.

  As the phosphoric acid compound, one or more of trialkyl phosphates such as trimethyl phosphate and triethyl phosphate are preferably used. These are preferably added in an amount of 0.0001 mol% or more and 0.005 mol% or less, and 0.0003 mol% or more and 0.003 mol% or less, based on all hydroxy compound components used in the production of the polycarbonate resin. Is more preferable. When the addition amount of the phosphorus compound is less than the lower limit, the effect of preventing coloring is small, and when the addition amount is more than the upper limit, the transparency is lowered, or conversely, the coloring is promoted or the heat resistance is lowered.

  Further, as the phosphorous acid compound, the following thermal stabilizer can be arbitrarily selected and used, and in particular, trimethyl phosphite, triethyl phosphite, trisnonylphenyl phosphite, trimethyl phosphate, tris (2, 4 One or more of -di-tert-butylphenyl) phosphite and bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite can be suitably used. These phosphite compounds are preferably added in an amount of 0.0001 mol% to 0.005 mol%, based on the total hydroxy compound components used in the production of the polycarbonate resin, and are 0.0003 mol% to 0.003 mol%. % Or less is more preferable. If the addition amount of the phosphorous acid compound is less than the lower limit, the effect of preventing coloring is small, and if it is more than the upper limit, the transparency may be reduced, or conversely, the coloring may be promoted or the heat resistance may be reduced. Sometimes.

  The phosphoric acid compound and the phosphorous acid compound can be added in combination, but the addition amount in that case is the total amount of the phosphoric acid compound and the phosphorous acid compound, and the total hydroxy compound component described above, The content is preferably 0.0001 mol% or more and 0.005 mol% or less, more preferably 0.0003 mol% or more and 0.003 mol% or less. If this addition amount is less than the lower limit, the effect of preventing coloring is small, and if it is more than the upper limit, it may cause a decrease in transparency, or conversely promote coloring or reduce heat resistance. .

[Antioxidant]
The polycarbonate resin unstretched film of the present invention preferably contains an antioxidant. By containing the antioxidant, the coloring suppression effect of the film is favorably exhibited. Here, the content of the antioxidant in the polycarbonate resin unstretched film of the present invention (that is, the content in the polycarbonate resin composition that is an extrusion molding material of the polycarbonate resin unstretched film of the present invention) is 100 weight of the polycarbonate resin. The amount is preferably 0.0001 to 1 part by weight, more preferably 0.0001 to 0.1 part by weight, and particularly preferably 0.0002 to 0.01 part by weight with respect to part.

  If the content of the antioxidant is 0.0001 part by weight or more, it is preferable because the effect of suppressing coloration when receiving heat history is sufficient. Moreover, if the content of the antioxidant is 1 part by weight or less, deposits are accumulated on the die or roll during the extrusion molding to cause contamination, or they are transferred to the product and the appearance shape is impaired. May cause defects such as contamination by foreign matter, bleed out on the surface of the product for a long time, impairing the appearance of the product, and the resulting polycarbonate resin unstretched film may be colored or lightened. Is preferable because it is small.

  The antioxidant is preferably at least one selected from the group consisting of phenolic antioxidants, phosphite antioxidants, and sulfur antioxidants, and phenolic antioxidants and / or phosphites. More preferred are system antioxidants. Of these, the combined use of a phenolic antioxidant and a phosphite antioxidant is effective.

  Examples of phenolic antioxidants include pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-laurylthiopropionate), glycerol-3-stearylthiopropionate, 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], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,3,5-trimethyl- , 4,6-Tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, N, N-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide) 3,5-di-tert-butyl-4-hydroxy-benzylphosphonate-diethyl ester, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 4,4′-biphenylenediphosphinic acid tetrakis (2,4-di-tert-butylphenyl) and 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.

  Among these compounds, an aromatic monohydroxy compound substituted with one or more alkyl groups having 5 or more carbon atoms is preferable. Specifically, octadecyl-3- (3,5-di-tert-butyl-4- Hydroxyphenyl) propionate, pentaerythrityl-tetrakis {3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate}, 1,6-hexanediol-bis [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 and the like, Lithyl-tetrakis {3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate is more preferred

  Examples of the phosphite antioxidant include triphenyl phosphite, tris (nonylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tridecyl phosphite, trioctyl phosphite, Trioctadecyl phosphite, didecyl monophenyl phosphite, dioctyl monophenyl phosphite, diisopropyl monophenyl phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, bis (2,6-di-) tert-butyl-4-methylphenyl) pentaerythritol diphosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, bis (nonylphenyl) pentaeri Li diphosphite, and bis (2,4-di -tert- butylphenyl) pentaerythritol diphosphite and distearyl pentaerythritol diphosphite.

  Among these, trisnonylphenyl phosphite, trimethyl phosphate, tris (2,4-di-tert-butylphenyl) phosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite and bis ( 2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite is preferred, and tris (2,4-di-tert-butylphenyl) phosphite is more preferred.

  Examples of the sulfur-based antioxidant include dilauryl-3,3′-thiodipropionate, ditridecyl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, diester Stearyl-3,3′-thiodipropionate, laurylstearyl-3,3′-thiodipropionate, pentaerythritol tetrakis (3-laurylthiopropionate), bis [2-methyl-4- (3 -Laurylthiopropionyloxy) -5-tert-butylphenyl] sulfide, octadecyl disulfide and mercaptobenzimidazole, 2-mercapto-6-methylbenzimidazole, 1,1′-thiobis (2-naphthol) and the like. Among the above, pentaerythritol tetrakis (3-lauryl thiopropionate) is preferable.

  In the present invention, the blending time and blending method of the antioxidant to be blended with the polycarbonate resin are not particularly limited. As the blending time, for example, when the polycarbonate resin is produced by the transesterification method, at the end of the polymerization reaction; in addition, regardless of the polymerization method, the polycarbonate resin melted during the kneading of the polycarbonate resin and other compounding agents. When blending and kneading with a solid state polycarbonate resin such as pellets or powder using an extruder or the like.

  As a blending method, for example, a method in which an antioxidant is directly mixed or kneaded with a polycarbonate resin; a method in which a small amount of a polycarbonate resin or other resin or the like is mixed with a high-concentration master batch prepared using an antioxidant; Is mentioned.

[Hindered amine stabilizer]
The polycarbonate resin unstretched film of the present invention preferably contains a hindered amine stabilizer.

  In the conventional polycarbonate resin using bisphenol A as the main dihydroxy compound raw material, it may be easily decomposed when an additive showing basicity like a hindered amine stabilizer is added. A low basic basic additive was selected and a small amount had to be added. However, the polycarbonate resin used in the present invention is very unlikely to undergo degradation and degradation even when a hindered amine stabilizer is added, and there is no particular limitation on the type. This is presumed to be due to the fact that the dihydroxy compound represented by the formula (1) is not a phenolic hydroxy group but an alcoholic hydroxy group is selected as the main component, so that it is not easily attacked by basic additives. The

  The content of the hindered amine stabilizer in the polycarbonate resin unstretched film of the present invention (that is, the content in the polycarbonate resin composition that is an extrusion molding material of the polycarbonate resin unstretched film of the present invention) is 100 parts by weight of the polycarbonate resin. On the other hand, it is usually preferably 0.0001 to 1 part by weight, more preferably 0.0001 to 0.1 part by weight, and particularly preferably 0.0002 to 0.01 part by weight.

  If the content of the hindered amine stabilizer is 0.0001 part by weight or more, the effect of improving light resistance is sufficiently obtained, which is preferable. Moreover, if the content of the hindered amine stabilizer is 1 part by weight or less, deposits may accumulate on the die or roll during the extrusion molding, or they may be transferred to the product and the appearance shape may be impaired. This may cause defects such as contamination of the product and cause foreign matter defects, bleed out on the product surface for a long time and damage the appearance of the product, or the resulting polycarbonate resin unstretched film may be colored or lightened. This is preferable because the fear is small.

  Examples of the hindered amine stabilizer include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis- (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, Poly [{6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl ) Imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}], N, N′-bis (3-aminopropyl) ethylenediamine-2,4-bis [N-butyl- N- (1,2,2,6,6-pentamethyl-4-piperidylamino) -6-chloro-1,3,5-triazine condensate and dibutylamine 1,3,5-triazine N, N ′ -Screws (2, 2, , 6) - polycondensate of tetramethyl-4-piperidyl-1,6-hexamethylenediamine and N-(2,2,6,6-tetramethyl-4-piperidyl) butylamine, and the like.

  These hindered amine stabilizers may be used in combination of two or more. Of these, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate and bis- (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate are preferred.

  In the present invention, the blending time and blending method of the hindered amine stabilizer to be blended with the polycarbonate resin are not particularly limited. As the blending time, for example, when the polycarbonate resin is produced by the transesterification method, at the end of the polymerization reaction; in addition, regardless of the polymerization method, the polycarbonate resin melted during the kneading of the polycarbonate resin and other compounding agents. When blending and kneading with a solid state polycarbonate resin such as pellets or powder using an extruder or the like.

  As a blending method, for example, a method in which a hindered amine stabilizer is directly mixed or kneaded with a polycarbonate resin; a method in which a small concentration of a polycarbonate resin or other resin is mixed with a hindered amine stabilizer as a high concentration master batch And so on.

[Acid compound or derivative thereof]
The polycarbonate resin unstretched film of the present invention may contain an acidic compound or a derivative thereof. The compounding amount of the acidic compound or derivative thereof in the polycarbonate resin unstretched film of the present invention (that is, the content in the polycarbonate resin composition that is an extrusion molding material of the polycarbonate resin unstretched film of the present invention) is 100 parts by weight of the polycarbonate resin. Is preferably 0.00001 part by weight or more and 0.1 part by weight or less, more preferably 0.0001 part by weight or more and 0.01 part by weight or less, and still more preferably 0.0002 part by weight. Part to 0.001 part by weight.

  If the compounding amount of the acidic compound or derivative thereof is 0.00001 part by weight or more, it is possible to sufficiently suppress coloring when the residence time of the polycarbonate resin composition is increased during extrusion molding. preferable. Moreover, if the compounding quantity of an acidic compound is 0.1 weight part or less, since there is little possibility that the hydrolysis resistance of a polycarbonate resin composition may fall, it is preferable.

  Examples of acidic compounds or derivatives thereof include hydrochloric acid, nitric acid, boric acid, sulfuric acid, sulfurous acid, phosphoric acid, phosphorous acid, hypophosphorous acid, polyphosphoric acid, adipic acid, ascorbic acid, aspartic acid, azelaic acid, and adenosine phosphorus. Acid, benzoic acid, formic acid, valeric acid, citric acid, glycolic acid, glutamic acid, glutaric acid, cinnamic acid, succinic acid, acetic acid, tartaric acid, oxalic acid, p-toluenesulfinic acid, p-toluenesulfonic acid, naphthalenesulfonic acid Bronsted acids such as nicotinic acid, picric acid, picolinic acid, phthalic acid, terephthalic acid, propionic acid, benzenesulfinic acid, benzenesulfonic acid, malonic acid and maleic acid, and esters thereof. These may be used individually by 1 type and may be used in combination of 2 or more type.

  Among these acidic compounds or derivatives thereof, sulfonic acids or esters thereof are preferable, and p-toluenesulfonic acid, methyl p-toluenesulfonate, and butyl p-toluenesulfonate are particularly preferable.

  These acidic compounds can be added in the manufacturing process of a polycarbonate resin composition as a compound which neutralizes the basic transesterification catalyst used in the polycondensation reaction of the polycarbonate resin mentioned above.

[Other additive components]
The polycarbonate resin unstretched film of the present invention contains an antistatic agent, a release agent, an ultraviolet absorber, a light stabilizer, an inorganic filler, a colorant, design imparting particles and the like as long as the object of the present invention is not impaired. You may do it. Furthermore, a nucleating agent, a flame retardant, an impact modifier, a foaming agent, a dyeing pigment, and the like that are usually used in the resin composition may be included as long as the object of the present invention is not impaired.

  Further, in the polycarbonate resin non-stretched film of the present invention, the above polycarbonate resin is, for example, aromatic polycarbonate, aromatic polyester, aliphatic polyester, polyamide, polystyrene, polyolefin, acrylic, within the range not impairing the object of the present invention. It can also be used as a polymer alloy by kneading with one or more of resins, synthetic resins such as ABS and AS, and various elastomers and various core-shell rubbers.

[Polycarbonate resin unstretched film]
The polycarbonate resin unstretched film of the present invention is produced using the polycarbonate resin. At this time, various commonly used additives, specifically, antioxidants, anti-coloring agents, ultraviolet absorbers, flame retardants, mold release agents, lubricants, antistatic agents, etc., within a range that does not impair the effects of the present invention. May be added.

  The polycarbonate resin unstretched film of the present invention is produced by melt-extruding the polycarbonate resin. Examples of the extrusion molding method include a T-die molding method and an inflation molding method. In the present invention, it is preferable to select the T-die molding method as follows.

  First, the polycarbonate resin and various blended additives as needed, pellets prepared by adding various additives to the polycarbonate resin in advance, and high concentrations of various additives in advance to the polycarbonate resin A master batch pellet prepared by addition and a dry blend of the polycarbonate resin and the like are put into an extruder through a feeder, melt kneaded, and extruded while being formed into a film by a T-die. At this time, the set temperature of the extruder or T-die is usually preferably 200 ° C. or higher and 280 ° C. or lower, and more preferably 200 ° C. or higher and 250 ° C. or lower.

  The resin melt-extruded while being formed into a film is brought into contact with a cast roll and cooled, and further brought into contact with at least one subsequent cooling roll and taken out while being cooled to obtain a polycarbonate resin film used in the present invention. Can do. Further, the surface of the film can be smoothed using a touch roll, a touch belt or the like.

  Films that require extremely high thickness accuracy are usually required to have a mirror-like surface. In this case, it is preferable that at least one of the cast roll or the touch roll is a metal mirror roll, and the maximum height Rz of the surface measured according to JIS-B0601 (2001) is further measured for the mirror roll. It is preferable that it is 0.3 micrometer or less. Generally, if there are minute irregularities on the roll surface, the irregularities are transferred to the product film. In applications that require high-precision film thickness accuracy such as optical applications, the above range is preferable as the upper limit of the size of the micro unevenness on the roll surface because such transfer unevenness cannot be overlooked.

  The set temperature of the cast roll is preferably (Tg-50) ° C. or more and (Tg-5) ° C. or less with respect to the glass transition temperature (Tg (° C.)) of the polycarbonate resin. When the set temperature of the cast roll is lower than the lower limit, the close contact with the roll becomes insufficient, and there is a possibility that local cooling insufficiency, periodic thickness unevenness, sudden breakage and the like may occur. If the set temperature of the cast roll is equal to or higher than the above upper limit, there is a risk that peeling failure due to insufficient cooling, roll contamination, transfer of peeling marks, and the like may occur.

In the present invention, in this melt extrusion molding, a gear pump is provided between the extruder and the T die, and the outlet side resin pressure fluctuation of the gear pump is set to 0.1% or more and 10% or less per 30 minutes. The polycarbonate resin unstretched film of the present invention is produced. Usually, in a single-screw extruder or a twin-screw extruder, extrusion pulsation occurs due to the rotation of a screw. For this reason, it is preferable to offset extrusion pulsation by providing a two-gear pump or a three-gear pump.
Since the resin pressure fluctuation at the outlet side of the gear pump is 10% or less per 30 minutes, preferably 5% or less, the thickness in the flow direction of the film does not change abruptly, and fine adjustment during film forming operation There is also an advantage that the thickness can be easily controlled. On the other hand, it is very difficult in terms of equipment capacity to make the resin pressure fluctuation of the gear pump outlet per 30 minutes less than 0.1%, and the object of the present invention can be achieved even more than that.

The distance (air gap) between the lower end of the lip of the T die and the center contact position between the cooling roll and the film is preferably 10 mm or more and 60 mm or less.
When the air gap is 60 mm or less, it is difficult to be affected by disturbance factors such as wind and thermal convection. Furthermore, the amount of neck-in is reduced, the width of the ear generated at the end of the film is minimized, and the possibility that the thickness of the film fluctuates due to fluctuations in the size of the ear is reduced. On the other hand, in order to make the air gap less than 10 mm, when forming a film by sandwiching a cast roll and a touch roll, the tip of the base is manufactured to be extremely thin, or the base is installed with an inclination. Since a device is required, the facility design is very difficult, and the object of the present invention can be achieved even more than that.
In addition, a method of providing windbreak plates at both ends of the T die can be employed.

Moreover, it is preferable that the lip length in the film flow direction in the T die is 15 mm or more and 50 mm or less.
A lip length in the flow direction of 15 mm or more is preferable because it is excellent in rectification of the molten resin. In addition, it is preferable that the lip length in the flow direction is 50 mm or less because problems such as excessive increase in the resin pressure and coloring due to shearing heat generation do not occur.

Moreover, in the manufacturing method of the polycarbonate resin unstretched film of this invention, it is preferable that the neck-in rate of the width direction shall be 92% or more and 98% or less.
Here, the neck-in rate in the width direction is calculated by “the length in the width direction of the film immediately after film formation / the lip length in the width direction of the film in the T die × 100”.
In addition, the “film immediately after film formation” refers to a film that is not subjected to any processing such as slitting the end ears in the step of melt extrusion from a T-die and drawing the film in contact with a cooling roll. .
A neck-in rate of 92% or more is preferable because the width of the ears at the end of the film is minimized and the size of the ears is less likely to fluctuate. On the other hand, due to technical limitations in melt extrusion molding, the neck-in rate is usually 98% or less.

  The polycarbonate resin unstretched film produced by the method for producing a polycarbonate resin unstretched film according to the present invention has one end in the width direction of the film between two points 10% inside the film width from both ends in the width direction of the film. The value of “maximum value Tmax−minimum value Tmin” of the film thickness measured at an interval of 50 mm from the other end to the other end is 5% or less of the average value Ta and flows at the center in the width direction of the film. The value of “maximum value tmax−minimum value tmin” of the film thickness measured at intervals of 50 mm over 1 m in the direction is preferably 5% or less of the average value ta. In addition, film thickness is calculated | required by the method as described in an Example. In addition, the film at this time may be the “film immediately after film formation” or the “film just after film formation” having slits at the ends.

If the thickness variation in the width direction and the flow direction of the polycarbonate resin unstretched film is larger than the above range, it is difficult to apply to applications where extremely high thickness accuracy is required.
As means for achieving the thickness accuracy in the width direction and the flow direction, for example, the reduced viscosity of the polycarbonate resin, the range width thereof, the melt viscosity, the glass transition temperature, the general formula (5) when the polycarbonate resin is produced. In the means for adjusting the molar ratio of the carbonic acid diester represented by the formula (1) or the fluctuation range of the molar ratio within the range described in the present specification or the method for producing the film, the conditions are appropriately changed within the range described in the present specification. Means can be mentioned.

The polycarbonate resin non-stretched film produced by the method for producing a polycarbonate resin non-stretched film of the present invention is the center in the width direction of the film between two points 10% inside the film width from both ends in the width direction of the film. It is preferable that the average value Ta of the film thicknesses measured at intervals of 50 mm from both ends to 30 μm or more and 300 μm or less.
It is preferable that Ta is 30 μm or more because the handling property of the film is excellent. Further, it is preferable that Ta is 300 μm or less because it is possible to suppress wrinkles when the film is used as a wound layer body and to maintain a high total light transmittance.

The polycarbonate resin unstretched film produced by the method for producing a polycarbonate resin unstretched film of the present invention is an average value of film thicknesses measured at 50 mm intervals over 1 m in the flow direction at the center in the width direction of the film. It is preferable that ta is 30 μm or more and 300 μm or less.
In general, the values of Ta and ta are substantially equal.

  The polycarbonate resin unstretched film produced by the method for producing a polycarbonate resin unstretched film of the present invention preferably has a length in the width direction of 20 mm or more and 2000 mm or less. If the length in the width direction is 200 mm or more, productivity is high, and the ratio of the ears at both ends to the product portion is small, which is economical. Moreover, if it is 2000 mm or less, it will become easy to take out predetermined thickness precision in the full width except for both ends.

Further, the reduced viscosity retention rate of the film, calculated as the ratio of the reduced viscosity of the polycarbonate resin unstretched film produced by the method for producing the polycarbonate resin unstretched film of the present invention to the reduced viscosity of the polycarbonate resin used in the present invention, is 80% or more and 100% or less, and the reduced viscosity retention is more preferably 85% or more and 100% or less, and still more preferably 90% or more and 100% or less. A reduced viscosity retention of 80% or more is preferable because the polycarbonate resin used in the present invention is a polycarbonate resin unstretched film that is suppressed from being decomposed by a molding machine and has good mechanical properties.
The reduced viscosity of the unstretched polycarbonate resin film of the present invention is also measured by the same method as the reduced viscosity of the polycarbonate resin used in the present invention.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by a following example, unless the summary is exceeded.

[Evaluation method]
The physical properties or characteristics of the polycarbonate resin and the polycarbonate resin unstretched film were evaluated by the following methods.

(1) Glass transition temperature (Tg)
In accordance with JIS-K7121, using a differential scanning calorimeter (DSC220, manufactured by SII Nano Technology), measured by heating about 10 mg of polycarbonate resin at a heating rate of 10 ° C./min, Obtain the extrapolated glass transition start temperature, which is the temperature at the intersection of the straight line that extends the base line to the high temperature side and the tangent line drawn at the point where the slope of the stepwise change part of the glass transition is maximized, This was taken as the glass transition temperature.

(2) Measurement of film thickness Using a JIS first-class gold ruler, place marks at predetermined positions on the film at intervals of 50 mm, and use a contact thickness gauge (Mitutoyo, Digimatic Indicator ID-F125). The film thickness in the vicinity was measured.
The thickness accuracy in the width direction was measured at 50 mm intervals from one end of the film in the width direction to the other end between the two points 10% inside the film width from both ends in the width direction of the film. The thickness accuracy (%) in the width direction was calculated as a percentage by dividing the value of “maximum value Tmax−minimum value Tmin” of the film thickness by the average value Ta.
Regarding the thickness accuracy in the flow direction, the value of “maximum value tmax−minimum value tmin” of the film thickness measured at intervals of 50 mm over 1 m in the flow direction at the center in the width direction of the film is divided by the average value ta. The thickness accuracy (%) in the flow direction was calculated as a percentage.

(3) Measurement of reduced viscosity A polycarbonate resin or a polycarbonate resin unstretched film sample was dissolved using methylene chloride as a solvent to prepare a polycarbonate solution having a concentration of 0.6 g / dL. Moritomo Rika Kogyo Co., Ltd. using a Ubbelohde viscosity tube, was measured at a temperature of 20.0 ° C. ± 0.1 ° C., the following equation from the passing time t of the passing time t ₀ and a solution of solvent from (i) The relative viscosity η _rel was determined, and the specific viscosity η _sp was determined from the relative viscosity according to the following formula (ii).
η _rel = t / t ₀ (i)
η _sp = (η−η ₀ ) / η ₀ = η _rel −1 (ii)
The reduced viscosity η _sp / c was determined by dividing the specific viscosity by the concentration c (g / dL). The higher this value, the higher the molecular weight.

(4) Measurement of structural unit ratio and terminal phenyl group concentration derived from each dihydroxy compound in polycarbonate resin Each dihydroxy compound structural unit ratio in polycarbonate resin was obtained by weighing out 30 mg of polycarbonate resin to about 0.7 mL of deuterated chloroform. Dissolve it into a solution, put it in an NMR tube with an inner diameter of 5 mm, and use JNM-AL400 (resonance frequency 400 MHz) manufactured by JEOL Ltd. at ¹ H at room temperature.
NMR spectrum was measured. The structural unit ratio derived from each dihydroxy compound was determined from the signal intensity ratio based on the structural unit derived from each dihydroxy compound.

(5) Measurement of content of aromatic monohydroxy compound in polycarbonate resin After dissolving 1.25 g of polycarbonate resin sample in 7 ml of methylene chloride to make a solution, acetone is added so that the total amount becomes 25 ml, and reprecipitation treatment is performed. went. Next, the treatment liquid was filtered through a 0.2 μm disk filter and quantified by liquid chromatography.

  Moreover, the symbol of the compound used in the following manufacture examples and Examples is as follows.

ISB: Isosorbide (Rocket Fleure, trade name: POLYSORB)
CHDM: 1,4-cyclohexanedimethanol (manufactured by Shin Nippon Rika Co., Ltd., trade name: SKY CHDM)
・ DPC: Diphenyl carbonate (Mitsubishi Chemical Corporation)

Antioxidant 1: hindered phenolic antioxidant (manufactured by BASF Japan, trade name: Irganox 1010)
Antioxidant 2: Phosphite antioxidant (manufactured by ADEKA, trade name: ADK STAB 2112)
-Hindered amine stabilizer (manufactured by BASF Japan, trade name: Tinuvin 765)

[Production example: Production of polycarbonate resin]
[Production Example 1]
Raw material prepared every 6 hours so that the molar ratio of ISB / CHDM / DPC is 50/50 / 99.8 in a raw material preparation tank sufficiently substituted with nitrogen (oxygen concentration 0.0005 vol% to 0.001 vol%) Is continuously supplied to a first polymerization reactor having a heat medium jacket using oil as a heat medium, a heat medium internal coil, a stirring blade, a distillation pipe connected to a vacuum pump, and a condenser. At the same time, the calcium acetate monohydrate in an aqueous solution is continuously supplied from the catalyst supply pipe connected to the raw material supply pipe so as to be 1.25 × 10 ⁻⁶ mol (calcium metal atom equivalent) per 1 mol of all dihydroxy compounds. Supplied.
After mixing the raw material and catalyst aqueous solution by piping, install two pleated cylindrical type raw material filtration filters in the flow path to enter the first reactor, the upstream raw material filtration filter opening is 10 μm, downstream The mesh opening was 1 μm.

In the first polymerization reactor, the distillation pipe is provided with a reflux condenser using oil (inlet temperature 130 ° C.) as a refrigerant, and phenol and the like that are not condensed in the reflux condenser. In addition, a condenser using warm water (inlet temperature 45 ° C.) as a refrigerant was disposed.
While maintaining the rotation speed of the stirring blade of the first polymerization reactor to be constant, the inner temperature is 183 to 185 ° C., the pressure is 23 to 25 kPa, and the residence time is 1.4 to 1.5 hours. It was continuously extracted from the bottom and fed to the second polymerization reactor.

  Similar to the first polymerization reactor, the second polymerization reactor includes a heat medium jacket, a heat medium internal coil, a stirring blade, a distillation pipe connected to a vacuum pump, and a distillation pipe having a reflux condenser and a condenser. And controlled to be constant at an internal temperature of 211 to 213 ° C., a pressure of 13 to 14 kPa, and a residence time of 0.8 to 1 hour, and the reaction liquid is continuously withdrawn from the bottom of the reaction vessel, and a third polymerization reactor Supplied to.

  The third polymerization reactor is controlled so as to be constant at an internal temperature of 227 to 229 ° C., a pressure of 5 to 6 kPa, and a residence time of 1 to 1.1 hours, and the polycondensation reaction proceeds while distilling off by-product phenol. The reaction liquid is continuously withdrawn from the bottom of the reaction vessel, and a horizontal stirring reactor (fourth) having two horizontal rotating shafts and mutually discontinuous stirring blades mounted substantially perpendicular to the horizontal shaft. Polymerization reactor).

  In the fourth polymerization reactor, the internal temperature in the vicinity of the inlet is 227 to 228 ° C., the internal temperature in the vicinity of the outlet is 238 to 240 ° C., and the pressure of the stirring blade is within a range of 3 N · m. It was adjusted in the range of .50 kPa, the residence time was controlled to be 1.3 to 1.5 hours, and the polycondensation reaction was further advanced.

The obtained polycarbonate resin has an additive supply port and three vent ports, L / D = 42, and the kneading disk occupies 6% of the length of the elements constituting the entire screw of the extruder. The twin screw extruder was continuously fed with a gear pump (the other screw elements of the kneading disc consisted of full flight and seal ring).
In the extruder, 0.1% of water is supplied to the polycarbonate resin to be processed, and the vent port is connected to a vacuum pump and the pressure is reduced to 0.01 to 0.03 kPa. Was removed.

A side feeder is installed downstream of the water supply nozzle and the subsequent vent port, 0.1 parts by weight of the antioxidant 1 with respect to 100 parts by weight of the polycarbonate resin, 0.05 parts by weight of the antioxidant 2 and stearic acid. Monoglyceride (manufactured by Riken Vitamin Co., Ltd.) was continuously fed so as to be 0.3 parts by weight.
The barrel temperature of the extruder was set to 245 ° C. for the 4 blocks upstream, 225 ° C. for the 6 blocks downstream, and the screw rotation speed was 250 rotations. The polycarbonate resin treated by the extruder was supplied to a filter unit having a resin inlet at the bottom and an outlet at the top through a gear pump installed at the outlet.

A leaf disk filter (manufactured by Nippon Pole Co., Ltd.) having a mesh opening of 15 μm was mounted inside the filter unit to remove foreign substances in the polycarbonate resin. Before use, the filter was roasted at 310 ° C. for 40 hours in a water vapor atmosphere and then at 420 ° C. for 52 hours in an air atmosphere, cooled to room temperature, and then immersed in a 30% by weight nitric acid aqueous solution for 30 minutes. Then, an oxide film was formed, washed and dried. The filter unit was provided with a heater composed of a plurality of blocks, and each temperature was set to 230 to 240 ° C.
On the outlet side of the filter unit, a die was installed through a polymer pipe equipped with a heater composed of a plurality of blocks. The set temperature of the heater of the polymer pipe was set to 220 to 230 ° C, and the heater of the dice was set to 220 ° C. The polycarbonate resin was extracted in the form of a strand in a room maintained at a class 10000 cleanness from the die, solidified in a water tank, and pelletized with a rotary cutter.

  Continuous production was carried out for 20 hours, and the reduced viscosity and residual phenol of the obtained polycarbonate resin were measured at 1 hour, 6 hours, 11 hours and 16 hours. The results are shown in Table 1.

[Production Example 2]
The same procedure as in Production Example 1 was conducted except that the pressure was adjusted in the range of 0.10 to 1.00 kPa so that the stirring blade torque range of the fourth polymerization reactor was within the range of 5 N · m. The reduced viscosity and residual phenol of the obtained polycarbonate resin were measured at 1 hour, 6 hours, 11 hours, and 16 hours. The results are shown in Table 1.

[Production Example 3]
In a raw material preparation tank sufficiently substituted with nitrogen (oxygen concentration 0.0005 vol% to 0.001 vol%), the molar ratio of ISB / CHDM / DPC was adjusted to 50/50 / 100.0, and then 50/50 /99.8 every 6 hours, and the same procedure as in Production Example 1 was conducted except that the pressure of the fourth polymerization reactor was changed to 0.3 to 0.4 kPa. The reduced viscosity and residual phenol of the obtained polycarbonate resin were measured at 1 hour, 6 hours, 11 hours, and 16 hours. The results are shown in Table 1.

[Production Example 4]
The same procedure as in Production Example 1 was performed except that the vent port of the extruder was closed. The reduced viscosity and residual phenol of the obtained polycarbonate resin were measured at 1 hour, 6 hours, 11 hours, and 16 hours. The results are shown in Table 1.

[Production Example 5]
Calcium acetate monohydrate in an aqueous solution is continuously supplied so as to be 1.25 × 10 ⁻⁵ mol (calcium metal atom equivalent) per 1 mol of all dihydroxy compounds, and the stirring blade torque range of the fourth polymerization reactor Was performed in the same manner as in Production Example 1 except that the pressure was adjusted in the range of 5.00 to 3.00 kPa so as to be within the range of 3 N · m. The reduced viscosity and residual phenol of the obtained polycarbonate resin were measured at 1 hour, 6 hours, 11 hours, and 16 hours. The results are shown in Table 1.

[Production Example 6]
The same procedure as in Production Example 1 was performed except that the raw material was prepared so that the molar ratio of ISB / CHDM / DPC was 70/30 / 99.8. The reduced viscosity and residual phenol of the obtained polycarbonate resin were measured at 1 hour, 6 hours, 11 hours, and 16 hours. The results are shown in Table 1.

  The polycarbonate resin produced in Production Example 1 is designated as “PC1”, and the polycarbonate resin produced in Production Example 6 is designated as “PC2”. The glass transition temperature (Tg) of “PC1” was 100 ° C., and the glass transition temperature (Tg) of “PC2” was 120 ° C.

[Examples 1 , 3 and 4, Reference Examples 2 and 5 , Comparative Example 1]
Polycarbonate resin pellets are supplied to an extrusion film forming machine connected by a conduit in the order of a twin-screw extruder, gear pump, polymer filter, and T-die at a set temperature of 220 ° C, and touches at set temperatures of 70, 85, and 50 ° C from the upstream side. A roll, a cast roll (maximum surface height Rz = 0.3 μm) and a cooling roll were sequentially contacted to obtain a film continuously. About the obtained film, various physical properties etc. were evaluated with the said evaluation method. The results are shown in Table 2.

As shown in Examples 1 , 3 , and 4 of Table 2, the polycarbonate resin unstretched film of the present invention has extremely excellent thickness accuracy in both the width direction and the flow direction.

  On the other hand, in Comparative Example 1, the variation in thickness is large because the variation in the outlet-side resin pressure of the gear pump is too large. Therefore, it can be seen that the object of the present invention can be achieved only by combining the constituent features of the present invention.

Claims (3)

A method for producing a polycarbonate resin unstretched film by melt extrusion molding a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following formula (1), comprising: an extruder and a T die; A polycarbonate having a gear pump interposed therebetween, and producing a non-stretched polycarbonate resin film satisfying the following condition (I) , wherein the resin pressure fluctuation at the outlet side of the gear pump is 0.1% to 2.9 % per 30 minutes A method for producing an unstretched resin film.
Condition (I): “Maximum of film thickness measured at 50 mm intervals from one end to the other end in the width direction of the film between two points 10% inside the film width from both ends in the width direction of the film. The value of “value Tmax−minimum value Tmin” is 1.4% or less of the average value Ta,
At the center in the width direction of the film, the value of “maximum value tmax−minimum value tmin” of the film thickness measured at intervals of 50 mm over 1 m in the flow direction is 1.4% or less of the average value ta.

  The method for producing an unstretched polycarbonate resin film according to claim 1, wherein the reduced viscosity of the polycarbonate resin is 0.30 dL / g or more and 1.20 dL / g or less, and the range width of the reduced viscosity is 0.05 dL / g or less. .   The manufacturing method of the polycarbonate resin unstretched film of Claim 1 or 2 whose glass transition temperature of the said polycarbonate resin is 90 to 160 degreeC.