Hollow container and method for producing polycarbonate resin

Abstract

The invention provides a hollow container and a method for producing polycarbonate resin. The hollow container is a blow-molded body of a polycarbonate resin having a terminal group represented by formula (1) in which X1-X5 may be the same as or different from each other, and the ratio of the terminal group represented by formula (1) to the total terminal group of the polycarbonate resin is 0.024-1.338 mol%, and in the formula (1), X1-X5 may be the same as or different from each other, X1-X5 may be the same as or different from each other, and X1-X5 may be the same as or different from each other. The present invention relates to a polycarbonate resin having a viscosity average molecular weight of 14,000-30,000 inclusive and a terminal hydroxyl group concentration of 100-1,000 ppm by mass inclusive, characterized in that X1-X5 each independently represents a hydrogen atom or a C1-3 alkyl group, at least one of X1-X5 in formula (1) is a C1-3 alkyl group, * represents a bond to a polycarbonate resin chain, and the polycarbonate resin has a viscosity average molecular weight of 14,000-30,000 inclusive and a terminal hydroxyl group concentration of 100-1,000 ppm by mass inclusive.

Description

[0001] This application is a divisional application of Chinese patent application No. 202480002138.7, filed on March 15, 2024, entitled "Polycarbonate Resin and Method for Manufacturing the Same Thereof, and Polycarbonate Resin Composition". Technical Field

[0002] This invention relates to a polycarbonate resin with excellent heat resistance (damp heat stability) and a method for manufacturing the same, which further reduces odor during melt molding or in the resulting molded article. More specifically, this invention relates to a polycarbonate resin suitable for use in food containers, etc., and a method for manufacturing the same. Background Technology

[0003] Polycarbonate resins, especially aromatic polycarbonate resins, are resins with excellent mechanical properties such as heat resistance and impact resistance, excellent dimensional stability, and excellent transparency, and are used in a variety of applications.

[0004] Polycarbonate resins are manufactured through processes such as melt polymerization (transesterification) and phosgene polymerization (interfacial polymerization). Aromatic polycarbonate resins manufactured by melt polymerization have poor water resistance (humid heat stability) because they are formed by reacting aromatic dihydroxy compounds with carbonate diesters in a molten state.

[0005] One method for improving the water resistance of aromatic polycarbonate resins is to carry out an ester exchange reaction in the presence of a specific type of catalyst (such as a nitrogen-containing basic compound), and then use a specific compound to cap the hydroxyl end of the obtained polycarbonate resin (Patent Document 1).

[0006] In either the melt process or the phosgene process, the polycarbonate resin is manufactured as a crude polycarbonate resin (a polycarbonate resin composition containing impurities) containing volatile impurities such as unreacted raw materials, low molecular weight products, and reaction solvents. Phenol, used in the melt process, is an example of a low molecular weight product.

[0007] In the melt process, the phenol generated during the transesterification reaction is removed by distillation under reduced pressure. In this case, due to the equilibrium relationship between the liquid and gas phases of the reaction, residual phenol remains in the liquid phase and is contained within the polycarbonate resin.

[0008] As a method for removing such volatile impurities, the following methods are known, for example.

[0009] A method for supplying nitrogen and water to the extrusion mixing section of a melt extruder and performing depressurization treatment when granulating aromatic polycarbonate resin by melt extrusion (Patent Document 2, Patent Document 3).

[0010] Methods for adding saturated aliphatic hydrocarbons and aromatic hydrocarbons (Patent Document 4, Patent Document 5);

[0011] A method for supplying carbon dioxide under pressure and then depressurizing it (Patent Document 6);

[0012] A method for mixing polycarbonate resin and water at 0.3~10MPa and subjecting them to depressurization treatment using a multi-stage vented melt extruder (Patent Document 7).

[0013] Patent document 8 describes a method for adding an aromatic polycarbonate or its oligomer with a terminal group having a higher volume ratio than phenoxy groups during the manufacture of an aromatic polycarbonate resin, with the improvement of heat resistance as the research topic. However, no research was conducted on water resistance (humid heat stability) and residual volatile impurities.

[0014] Existing technical documents

[0015] Patent documents

[0016] Patent Document 1: Japanese Patent Application Publication No. 2-175723

[0017] Patent Document 2: Japanese Patent Application Publication No. 9-59367

[0018] Patent Document 3: Japanese Patent Application Publication No. 9-59368

[0019] Patent Document 4: Japanese Patent Application Publication No. 9-67433

[0020] Patent Document 5: Japanese Patent Application Publication No. 9-157375

[0021] Patent Document 6: Japanese Patent Application Publication No. 2000-302879

[0022] Patent Document 7: Japanese Patent Application Publication No. 2001-31753

[0023] Patent Document 8: Japanese Patent No. 4267344 Summary of the Invention

[0024] The problem that the invention aims to solve

[0025] Aromatic polycarbonate resins manufactured by melt processing tend to have high melt viscosity. Therefore, it is sometimes difficult to completely remove volatile impurities that remain with the manufactured aromatic polycarbonate resin.

[0026] Furthermore, aromatic polycarbonate resins can produce odors during melt molding due to volatile impurities. As a result, the molded products also retain odors. Therefore, their use in food containers and similar applications is sometimes limited.

[0027] Food containers and similar products are often exposed to high temperatures and humidity. Therefore, molded products made of aromatic polycarbonate resins sometimes exhibit defects such as whitening within a short period of time due to their low heat resistance (hygrothermal stability).

[0028] The objective of this invention is to provide a polycarbonate resin or polycarbonate resin composition that can reduce the amount of volatile impurities that may be generated during manufacturing, has excellent heat resistance (damp heat stability), is unlikely to cause whitening even when exposed to high temperature and high humidity conditions, and suppresses the odor of the molded article obtained during melt molding.

[0029] Methods for solving problems

[0030] The inventors have discovered that by setting a portion of the end groups of the polycarbonate resin as specific end groups, a polycarbonate resin that meets the above-mentioned objectives can be obtained.

[0031] The main points of this invention are as follows.

[0032] [1] A polycarbonate resin having terminal groups represented by the following formula (1), wherein the proportion of the terminal groups represented by the following formula (1) to all terminal groups is 0.024 to 4.0 mol.

[0033] [Chemistry 1]

[0034]

[0035] (In the above formula (1), X) 1 ~X 5 They can be the same or different, each independently representing an alkyl group with 1 to 3 hydrogen atoms or carbon atoms. Among them, X in formula (1) 1 ~X 5 At least one of them is an alkyl group having 1 to 3 carbon atoms. * indicates a bond with the polycarbonate resin chain.

[0036] [2] According to the polycarbonate resin described in [1], the proportion of the terminal group represented by the above formula (1) to all the terminal groups of the above polycarbonate resin is 0.024 to 2.0 mol.

[0037] [3] According to the polycarbonate resin described in [2], the ratio of the terminal group represented by the above formula (1) to all the terminal groups of the above polycarbonate resin is 0.030 to 2.0 mol.

[0038] [4] The polycarbonate resin according to any one of [1] to [3] has a terminal group represented by the above formula (1) as methylphenoxy.

[0039] [5] The polycarbonate resin according to any one of [1] to [4] is a transesterification product of a dihydroxy compound and a diester, wherein the dihydroxy compound comprises at least one selected from the group consisting of aromatic dihydroxy compounds, aliphatic dihydroxy compounds and alicyclic dihydroxy compounds.

[0040] [6] According to the polycarbonate resin described in [5], the aromatic dihydroxy compound is bisphenol A.

[0041] [7] The total amount of compounds represented by the following formulas (A) to (E) in the hydrolysate obtained by hydrolyzing the polycarbonate resin according to any one of [1] to [6] is 500 to 6,000 ppm by mass relative to the polycarbonate resin.

[0042] [Chemistry 2]

[0043]

[0044] (R in the above formula (A)) 1 R in equation (B) 2 R in equation (C) 3 R 4 R in formula (D) 5 R 6 Each can independently represent a hydrogen atom or a methyl group.

[0045] [8] According to the polycarbonate resin described in [7], the total amount of the compounds represented by the above formulas (A) to (E) in the hydrolysate obtained by hydrolyzing the above polycarbonate resin is 2,000 to 6,000 ppm by mass relative to the polycarbonate resin.

[0046] [9] According to the polycarbonate resin described in [8], the total amount of the compounds represented by the above formulas (A) to (E) obtained by hydrolyzing the above polycarbonate resin is 3,000 to 6,000 ppm by mass relative to the polycarbonate resin.

[0047]

[10] The polycarbonate resin according to any one of [1] to [9] has a terminal hydroxyl concentration of 1000 ppm by mass or less.

[0048]

[11] According to the polycarbonate resin described in

[10] , the concentration of terminal hydroxyl groups in the polycarbonate resin is less than 700 ppm by mass.

[0049]

[12] The polycarbonate resin according to any one of [1] to

[11] has a viscosity-average molecular weight of 14,000 or more and 30,000 or less.

[0050]

[13] The polycarbonate resin according to any one of [1] to

[12] is characterized in that the total amount of the compound represented by the following formula (2) in the hydrolysate obtained by hydrolyzing the above-mentioned polycarbonate resin is 4 to 1,500 ppm by mass relative to the polycarbonate resin.

[0051] [Chemistry 3]

[0052]

[0053] (In the above formula (2), X) 1 ~X 5 respectively with X in the above formula (1) 1 ~X 5 Synonyms.

[0054]

[14] The polycarbonate resin according to any one of [1] to

[13] has a Δ haze of 4.3 or less after molding the polycarbonate resin under the following molding conditions I at 120°C and saturated water vapor for 100 hours.

[0055] (Forming condition I)

[0056] After drying the polycarbonate resin granules at 120°C for 4 hours, they were injection molded using an injection molding machine at a barrel temperature of 350°C and a mold temperature of 140°C to obtain a plate-shaped molded body with a thickness of 3mm, a length of 25mm, and a width of 25mm.

[0057]

[15] A polycarbonate resin composition comprising any one of [1] to

[14] .

[0058]

[16] According to the polycarbonate resin composition of

[15] , the content of aromatic monohydroxy compounds in the polycarbonate resin composition is less than 20 ppm by mass.

[0059]

[17] A method for manufacturing a polycarbonate resin, characterized in that it includes: a reaction step of obtaining the polycarbonate resin described in any one of [1] to

[14] by transesterification treatment of a dihydroxy compound and a diester.

[0060] The aforementioned diesters include the diesters represented by the following formula (3).

[0061] [Chemistry 4]

[0062]

[0063] (In the above formula (3), X) 1A ~X 5A and X 1B ~X5B They can be the same or different, each independently representing an alkyl group with 1 to 3 hydrogen atoms or carbon atoms. Among them, X in formula (3) 1A ~X 5A and X 1B ~X 5B At least one of them is an alkyl group having 1 to 3 carbon atoms.

[0064]

[18] The method for manufacturing polycarbonate resin according to

[17] is characterized in that the above-mentioned diester further comprises diphenyl carbonate, and the ratio of the amount of diester represented by the above formula (3) to the amount of diphenyl carbonate is 80 to 35,000 ppm by mass.

[0065]

[19] The method for manufacturing polycarbonate resin according to

[17] is characterized in that the carbonate diester represented by the above formula (3) is methyl phenyl phenyl carbonate.

[0066]

[20] The method for manufacturing polycarbonate resin according to any one of

[17] to

[19] is characterized in that the dihydroxy compound comprises at least one selected from the group consisting of aromatic dihydroxy compounds, aliphatic dihydroxy compounds and alicyclic dihydroxy compounds.

[0067]

[21] The method for manufacturing polycarbonate resin according to

[20] is characterized in that the dihydroxy compound is bisphenol A.

[0068]

[22] The method for manufacturing polycarbonate resin according to any one of

[17] to

[21] is characterized in that it further includes a step of devolatilizing the polycarbonate resin using a twin-screw extruder with a vent after the above reaction step.

[0069]

[23] The method for manufacturing polycarbonate resin according to any one of

[17] to

[22] is characterized in that, in the above-described reaction step,

[0070] The above reaction was carried out in the presence of an transesterification catalyst.

[0071] After the above reaction treatment, a further catalyst deactivation treatment is carried out by adding 5 to 15 molar equivalents of catalyst deactivator relative to 1 mole of the above transesterification catalyst.

[0072]

[24] A hollow container, which is a blow-molded polycarbonate resin as described in any one of [1] to

[14] .

[0073]

[25] A hollow container, which is a blow-molded body of the polycarbonate resin composition described in

[15] or

[16] .

[0074]

[26] The hollow container described in

[24] is a dairy bottle, a soft drink bottle or a water bottle.

[0075]

[27] A sheet material, which is a molded body of polycarbonate resin as described in any one of [1] to

[14] .

[0076]

[28] A sheet material which is a molded body of the polycarbonate resin composition described in

[15] or

[16] .

[0077] Invention Effects

[0078] The polycarbonate resin of this invention can reduce the amount of volatile impurities that may be generated during manufacturing, and has excellent heat resistance (damp heat stability), making it difficult to cause whitening even when exposed to high temperature and high humidity conditions. In addition, it can also suppress the odor of the molded articles obtained during melt molding.

[0079] The polycarbonate resin of the present invention, with its excellent heat resistance (damp heat stability) and odor suppression, is particularly suitable for use in hollow containers such as food containers. Attached Figure Description

[0080] [ Figure 1 ] Figure 1 This is a system diagram illustrating an example of the transesterification and polycondensation reaction processes in the manufacture of polycarbonate resin according to one embodiment of the present invention. Detailed Implementation

[0081] The embodiments of the present invention will now be described in detail. However, each embodiment and its combination are merely examples, and appropriate additions, omissions, substitutions, and other modifications can be made to the structure without departing from the spirit of this disclosure. This specification is not limited to the embodiments.

[0082] Furthermore, the various methods disclosed in this specification can also be combined with any other features disclosed in this specification.

[0083] Furthermore, in this specification, "X~Y" indicating a range means "X or more, Y or less". Additionally, when the numerical ranges represented by "X~Y" or "X or more, Y or less" are described in stages (e.g., in a preferred order), the upper and lower limits of each numerical range can be arbitrarily combined.

[0084] Furthermore, in this specification, the phrase "select one or more from the group consisting of X, Y, and Z" refers to any one of X, Y, Z, the combination of X and Y, the combination of X and Z, the combination of Y and Z, or the combination of X, Y, and Z.

[0085] [Polycarbonate resin]

[0086] The polycarbonate resin (hereinafter also simply referred to as "polycarbonate resin") of one embodiment of the present invention is characterized in that it has terminal groups represented by the following formula (1), wherein the proportion of the terminal groups represented by the following formula (1) to all terminal groups is 0.024 to 4.0 mol.

[0087] [Chemistry 5]

[0088]

[0089] In the above formula (1), X 1 ~X 5 They can be the same or different, each independently representing an alkyl group with 1 to 3 hydrogen atoms or carbon atoms. Among them, X in formula (1) 1 ~X 5 At least one of them is an alkyl group having 1 to 3 carbon atoms. * indicates a bond with the polycarbonate resin chain.

[0090] Hereinafter, the terminal group represented by the above formula (1) is sometimes referred to as "terminal group (1)". In addition, the ratio (molar ratio) of terminal group (1) to all terminal groups of polycarbonate resin is sometimes referred to as "terminal group (1) / total terminal group ratio".

[0091] <Terminal group (1)>

[0092] In the above formula (1) representing the terminal group (1), X 1 ~X 5 They can be the same or different, each independently representing an alkyl group with 1 to 3 hydrogen atoms. X 1 ~X 5 At least one of them is an alkyl group having 1 to 3 carbon atoms.

[0093] As X 1 ~X 5 Alkyl groups, such as methyl, ethyl or propyl, etc.

[0094] From the viewpoint of the color tone of polycarbonate resin, regarding the terminal group (1), in the above formula (1), X is preferred. 1 ~X 5 At least one of them is an alkyl group having 1 to 3 carbon atoms, more preferably X 1 ~X 5 One or two of them are alkyl groups with 1 to 3 carbon atoms, and the X is a non-alkyl group. 1 ~X 5 It is a hydrogen atom. In particular, the terminal group (1) is preferably methylphenoxy, and especially preferably o-methylphenoxy.

[0095] Polycarbonate resins can have one terminal group (1) or X.1 ~X 5 Two or more different terminal groups (1).

[0096] <Ratio of terminal group (1) to all terminal groups>

[0097] The ratio of the terminal group (1) to 100 mol% of all terminal groups of the polycarbonate resin (terminal group (1) / total terminal group ratio) represented by the above formula (1) can be 4.5 mol% or less, preferably 4.0 mol% or less, more preferably 2.0 mol% or less, and even more preferably 1.5 mol% or less. If the ratio of terminal group (1) / total terminal group exceeds 5 mol%, the polycarbonate resin may yellow, and its heat resistance (humid heat stability) may deteriorate. On the other hand, the ratio of terminal group (1) / total terminal group of the polycarbonate resin is preferably 0.024 mol% or more, more preferably 0.03 mol% or more, even more preferably 0.040 mol% or more, and particularly preferably 0.060 mol% or more. As described above, the upper and lower limits of the numerical range in this specification can be arbitrarily combined. As long as the ratio is specified, the upper and lower limits can be arbitrarily combined, such as 0.024~4.0 mol%, 0.024~2.0 mol%, or 0.03~2.0 mol%. When the ratio of the terminal group (1) to all terminal groups is less than 0.021 mol%, the amount of volatile impurities that may be generated during manufacturing increases, the heat resistance (damp heat stability) deteriorates, and there is also the possibility of odor problems.

[0098] There are no particular limitations on the method of controlling the ratio of terminal groups (1) to all terminal groups of polycarbonate resin within the above range. When manufacturing polycarbonate resin by transesterification reaction of dihydroxy compound with diester, the following methods can be listed as an example.

[0099] (I) As a diester, a diester containing the diester represented by the following formula (3) (hereinafter sometimes referred to as "diester (3)") is used, and the amount of diester (3) in the raw diester is controlled. Alternatively, diester (3) is added to the raw diester in a desired amount.

[0100] [Chemistry 6]

[0101]

[0102] In the above formula (3), X 1A ~X 5A and X 1B ~X 5B They can be the same or different, each independently representing an alkyl group with 1 to 3 hydrogen atoms or carbon atoms. Among them, X in formula (3) 1A ~X 5A and X1B ~X 5B At least one of them is an alkyl group having 1 to 3 carbon atoms.

[0103] In equation (3), X 1A ~X 5A and X 1B ~X 5B respectively with X in the above formula (1) 1 ~X 5 Similarly, the preferred method is also the same.

[0104] (II) Control the content of the compound represented by the following formula (2) (hereinafter sometimes referred to as "compound (2)") contained in the polycarbonate resin raw material, especially the dihydroxy compound of the raw material. Alternatively, add compound (2) to the polycarbonate resin raw material in a desired amount.

[0105] [Chemistry 7]

[0106]

[0107] In equation (2) above, X 1 ~X 5 respectively with X in the above formula (1) 1 ~X 5 Similarly, the preferred method is also the same.

[0108] The amount of terminal groups (1) in the polycarbonate resin can be calculated from the amount of compound (2) in the hydrolysate obtained by hydrolyzing the polycarbonate resin, as shown in one of the examples described later. In fact, it can be calculated from the amount of compound (2) determined by hydrolyzing the polycarbonate resin. When the amount of terminal groups (1) cannot be calculated from the amount of compound (2) in the hydrolysate obtained by hydrolyzing the polycarbonate resin, it can also be determined by directly analyzing the polycarbonate resin by NMR and measuring the amount of structural units derived from compound (2).

[0109] The specific determination and calculation method of the ratio of terminal group (1) to all terminal groups is shown in one of the examples described below.

[0110] <Specific amounts of byproducts in the hydrolysate of polycarbonate resin>

[0111] The total amount (hereinafter, sometimes referred to as "specific byproduct amount") of the compounds represented by (A) to (E) below in the hydrolysate obtained by hydrolyzing polycarbonate resin is preferably 500 to 6,000 ppm by mass relative to the polycarbonate resin.

[0112] [Chemistry 8]

[0113]

[0114] R in the above formula (A) 1 R in equation (B) 2 R in equation (C) 3 and R 4 and R in equation (D) 5 and R 6 Each can be used independently to represent a hydrogen atom or a methyl group.

[0115] If the amount of a specific byproduct in the hydrolysate obtained by hydrolyzing polycarbonate resin is less than 6,000 ppm by mass, the formation of gel-like substances is easily suppressed, and foreign matter is less likely to be observed in the molded article during polycarbonate resin molding, thus preventing appearance defects. From this point of view, the amount of this specific byproduct is more preferably less than 5,000 ppm by mass. On the other hand, the total amount of this specific byproduct is preferably more than 500 ppm by mass, more preferably more than 1,000 ppm by mass, further preferably more than 1,500 ppm by mass, even more preferably more than 2,000 ppm by mass, particularly preferably more than 2,500 ppm by mass, especially preferably more than 3,000 ppm by mass, and most preferably more than 3,500 ppm by mass. If the amount of the specific byproduct is set to less than 500 ppm by mass, the polymerization activity becomes low, requiring a longer reaction time, which may result in a deterioration of the color of the polycarbonate resin.

[0116] Methods for controlling the amount of specific byproducts in the hydrolysate obtained by hydrolyzing polycarbonate resin within the aforementioned preferred range include, for example, adjusting the amount of catalyst in the transesterification catalyst, adjusting the temperature (internal temperature) of the final reactor, adjusting the reaction time in the final reactor, or adjusting the concentration of terminal hydroxyl groups in the polycarbonate resin. That is, by reducing the amount of catalyst in the transesterification catalyst, the temperature (internal temperature) of the final reactor, or the reaction time in the final reactor, the formation reaction of specific byproducts can be suppressed, thereby reducing the amount of specific byproducts in the hydrolysate obtained by hydrolyzing polycarbonate resin. If the concentration of terminal hydroxyl groups in the polycarbonate resin is too low, the transesterification reaction rate decreases, leading to an increase in the temperature (internal temperature) of the final reactor and the reaction time in the final reactor, which in turn increases the amount of specific byproducts in the hydrolysate obtained by hydrolyzing polycarbonate resin. In particular, the amount of catalyst in the transesterification catalyst, the temperature (internal temperature) of the final reactor, or the concentration of terminal hydroxyl groups in the polycarbonate resin is important; by selecting from the various preferred ranges described below, the amount of specific byproducts can be controlled within the aforementioned preferred range.

[0117] The amount of a specific byproduct in the hydrolysate obtained by hydrolyzing polycarbonate resin was determined by the method described in one of the examples below.

[0118] <Content of compound (2) in the hydrolysate of polycarbonate resin>

[0119] The content (total amount) of the compound (2) in the hydrolysate obtained by hydrolyzing polycarbonate resin is preferably 1,500 ppm by mass or less, more preferably 1,100 ppm by mass or less, and even more preferably 300 ppm by mass or less, relative to the polycarbonate resin. If the content of compound (2) in the hydrolysate is below the above-mentioned upper limit, yellowing of the polycarbonate resin can be suppressed, and heat resistance (damp heat stability) also becomes good. The lower limit of the content (total amount) of compound (2) in the hydrolysate obtained by hydrolyzing polycarbonate resin is preferably 4 ppm by mass or more, more preferably 6 ppm by mass or more, and even more preferably 10 ppm by mass or more, relative to the polycarbonate resin. If the content of compound (2) in the hydrolysate is above the above-mentioned lower limit, the amount of volatile impurities that may be generated during the manufacture of the polycarbonate resin can be reduced, and heat resistance (damp heat stability) becomes good.

[0120] Methods for controlling the content of compound (2) in the hydrolysate of polycarbonate resin include controlling the amount of the aforementioned diester (3) contained in the diester used in the manufacture of polycarbonate resin, or adding diester (3) as a raw material for transesterification reaction.

[0121] The hydrolysis method of polycarbonate resin and the method for determining the content of compound (2) in the hydrolysate of polycarbonate resin are described in one of the examples below.

[0122] <Concentration of terminal hydroxyl groups in polycarbonate resin>

[0123] The concentration of terminal hydroxyl groups in the polycarbonate resin is not particularly limited, but is preferably 1000 ppm by mass or less, more preferably 800 ppm by mass or less, further preferably 700 ppm by mass or less, particularly preferably 600 ppm by mass or less, especially preferably 500 ppm by mass or less, and most preferably 450 ppm by mass or less. If the concentration of terminal hydroxyl groups is below the above upper limit, the amount of volatile impurities such as unreacted raw materials or low molecular weight products that may be generated during manufacturing can be reduced, and the odor during melt molding and the odor of the obtained molded article can be suppressed. Furthermore, if the concentration of terminal hydroxyl groups is below the above upper limit, the molecular weight reduction of the obtained molded article when exposed to high temperature and high humidity can be suppressed, preventing whitening or easy breakage of the molded article due to the reduction in molecular weight. On the other hand, the lower limit of the concentration of terminal hydroxyl groups in the polycarbonate resin is generally 100 ppm by mass or more, preferably 200 ppm by mass or more. If the concentration of terminal hydroxyl groups is above the above lower limit, the transesterification and polycondensation reactions during the manufacturing of the polycarbonate resin will not be slowed down, and the desired viscosity-average molecular weight of the polycarbonate resin can be obtained without setting high temperature, high vacuum, and long residence time. Therefore, it can inhibit the yellowing of polycarbonate resin.

[0124] As a method for controlling the concentration of terminal hydroxyl groups in polycarbonate resin within the aforementioned preferred range, the following method can be employed: In the manufacture of polycarbonate resin, as described later, the mixing ratio of diaryl carbonate and aromatic dihydroxy compound supplied to the transesterification reaction is adjusted. Specifically, it is preferable to use 1.03 times (molar ratio) or more of diaryl carbonate relative to the aromatic dihydroxy compound, more preferably 1.04 times (molar ratio) or more. By using diaryl carbonate at or above the aforementioned lower limit, the concentration of terminal hydroxyl groups in the obtained aromatic polycarbonate resin can be suppressed to below or below the aforementioned upper limit. The upper limit of the amount of diaryl carbonate used relative to the aromatic dihydroxy compound is preferably 1.30 times (molar ratio) or less, more preferably 1.20 times (molar ratio) or less.

[0125] The concentration of terminal hydroxyl groups in aromatic polycarbonate resins is determined not only by the mixing ratio of diaryl carbonate to aromatic dihydroxy compounds, but also by the shape of the apparatus and operating conditions. Therefore, it is preferable to measure the actual concentration of terminal hydroxyl groups in the aromatic polycarbonate resins obtained and adjust the mixing ratio of diaryl carbonate to aromatic dihydroxy compounds appropriately based on the results.

[0126] The concentration of terminal hydroxyl groups in the polycarbonate resin was determined by the method described in one of the examples below.

[0127] Methods for controlling the concentration of terminal hydroxyl groups in polycarbonate resins are described later.

[0128] <Viscosity-average molecular weight of polycarbonate resin>

[0129] In the manufacturing process of polycarbonate resin, from the perspective of reducing the amount of the aforementioned volatile impurities, the polycarbonate resin preferably has low viscosity. From this viewpoint, the viscosity-average molecular weight of the polycarbonate resin that may be generated during manufacturing is preferably 30,000 or less, more preferably 28,000 or less, and even more preferably 27,000 or less. If the viscosity-average molecular weight is below the aforementioned upper limit, the volatilization of volatile impurities in the polycarbonate resin manufacturing process becomes easier, and the amount of volatile impurities that may be generated during manufacturing is easily reduced. Furthermore, if the viscosity-average molecular weight is below the aforementioned upper limit, the cross-linking reaction can be suppressed, and the formation of gel-like substances caused by the cross-linking reaction can be suppressed, thus preventing these gel-like substances from becoming foreign matter in the molded article and causing appearance defects. On the other hand, the lower limit of the viscosity-average molecular weight of the polycarbonate resin is generally 14,000 or more, preferably 15,000 or more, and more preferably 16,000 or more. If the viscosity-average molecular weight is above the aforementioned lower limit, the obtained molded article can be prevented from becoming brittle or easily breaking.

[0130] The viscosity-average molecular weight of the polycarbonate resin was determined by the method described in one of the examples below.

[0131] <Δhaze of polycarbonate resin after 100 hours at 120°C and saturated water vapor>

[0132] The Δhaze of the molded body obtained by molding polycarbonate resin under the following molding conditions I, after 100 hours at 120°C and saturated water vapor, is not particularly limited, but is more preferably 4.3 or less, further preferably 4.2 or less, and particularly preferably 4.1 or less. The lower limit of this Δhaze is not particularly limited, as long as it is 0 or more. If the Δhaze is below the upper limit of the above range, it indicates that the decrease in the molecular weight of the polymer can be suppressed, and the whitening of the board can be suppressed.

[0133] (Forming condition I)

[0134] After drying the polycarbonate resin granules at 120°C for 4 hours, they were injection molded using an injection molding machine at a barrel temperature of 350°C and a mold temperature of 140°C to obtain a plate-shaped molded body with a thickness of 3mm, a length of 25mm, and a width of 25mm.

[0135] The Δhaze of the polycarbonate resin was determined by the method described in one of the examples below.

[0136] [Manufacturing method of polycarbonate resin]

[0137] There are no particular limitations on the manufacturing method of polycarbonate resin. For example, it can be manufactured by the method shown below.

[0138] The polycarbonate resin is preferably a transesterification product of a dihydroxy compound and a diester, and more preferably it can be manufactured by a method comprising: a reaction step of obtaining the polycarbonate resin by transesterification treatment of a dihydroxy compound and a diester containing the above-mentioned diester (3).

[0139] In particular, as a diester, a diaryl carbonate is preferred, and as a dihydroxy compound, at least one selected from the group consisting of aromatic dihydroxy compounds, aliphatic dihydroxy compounds, and alicyclic dihydroxy compounds is preferred. It should be noted that in this specification, the statement "as A, at least one selected from the group consisting of B and C is used" is sometimes also expressed as "A includes at least one selected from the group consisting of B and C".

[0140] That is, the polycarbonate resin is preferably an aromatic polycarbonate resin manufactured by transesterification reaction of diaryl carbonate with an aromatic dihydroxy compound.

[0141] It should be noted that the above reaction process may include not only transesterification but also polycondensation reaction, as described later.

[0142] The following describes a method for manufacturing aromatic polycarbonate resin using diaryl carbonate as the diester and aromatic dihydroxy compound as the dihydroxy compound, illustrating a method for manufacturing polycarbonate resin. The method for manufacturing polycarbonate resin is not limited to any of the following methods.

[0143] The manufacture of aromatic polycarbonate resins is usually carried out by mixing aromatic dihydroxy compounds and diaryl carbonates as raw materials to prepare a raw material mixture, and then subjecting the raw material mixture to transesterification (transesterification treatment) and polycondensation (polycondensation treatment) in a polycondensation reactor in the presence of a transesterification catalyst.

[0144] The polycondensation treatment can be carried out in a batch, continuous, or combination thereof. In this embodiment, the raw material preparation and reaction processes are preferably carried out continuously. After the transesterification and polycondensation treatments, the process includes a step of removing unreacted raw materials and reaction byproducts from the polymerization reaction solution after the reaction is stopped; a step of adding heat stabilizers, release agents, or colorants; and a step of forming particles of a predetermined particle size as needed, thereby producing an aromatic polycarbonate resin.

[0145] <Diaryl carbonate>

[0146] Examples of diaryl carbonates include diphenyl carbonate (DPC) or dimethyl carbonate, which are substituted diphenyl carbonates. These diaryl carbonates can be used alone or in combination of two or more.

[0147] The aforementioned diaryl carbonate can preferably be replaced by a dicarboxylic acid or a dicarboxylic acid ester in an amount of 50 mol% or less, more preferably 30 mol% or less. Representative dicarboxylic acids or dicarboxylic acid esters include terephthalic acid, isophthalic acid, diphenyl terephthalate, or diphenyl isophthalate. When the diaryl carbonate is replaced by a dicarboxylic acid or a dicarboxylic acid ester, a polyester carbonate can be obtained.

[0148] The aforementioned diester (3) can be included in diaryl carbonate or added separately as a raw material for transesterification reaction.

[0149] There are no particular limitations on the method for changing the content of diester (3) in diaryl carbonate. For example, the content of diester (3) in diaryl carbonate can also be changed by changing the content of the above-mentioned compound (2) in the monohydroxy aryl compound used as a raw material for diaryl carbonate.

[0150] When diphenyl carbonate is used as a raw material, diaryl carbonate, the ratio of the amount of diester (3) to the amount of diphenyl carbonate is preferably 35,000 ppm by mass or less, more preferably 20,000 ppm by mass or less, and even more preferably 10,000 ppm by mass or less. If the ratio of diester (3) to diphenyl carbonate is below the above-mentioned upper limit, yellowing of the obtained polycarbonate resin can be suppressed, and the heat resistance (damp heat stability) becomes good. The lower limit of the ratio of diester (3) to diphenyl carbonate is preferably 80 ppm by mass or more, more preferably 200 ppm by mass or more, more preferably 400 ppm by mass or more, and even more preferably 550 ppm by mass or more. If the ratio of diester (3) to diphenyl carbonate is above the above-mentioned lower limit, the amount of volatile impurities that may be generated during manufacturing can be reduced, and the heat resistance (damp heat stability) becomes good.

[0151] As a diester (3), methyl phenyl carbonate is particularly preferred, and o-methyl phenyl carbonate is most preferred.

[0152] <Dihydroxy compounds>

[0153] Examples of dihydroxy compounds include aromatic dihydroxy compounds having two intramolecular hydroxyl groups, aliphatic dihydroxy compounds, or alicyclic dihydroxy compounds, with aromatic dihydroxy compounds being preferred. Among aromatic dihydroxy compounds, those having one or more aromatic rings intramolecularly and with each of the two hydroxyl groups bonded to an aromatic ring are preferred.

[0154] Specific examples of aromatic dihydroxy compounds include bis(4-hydroxydiphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxy-3-tert-butylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dibromophenyl)propane, 4,4-bis(4-hydroxyphenyl)heptane, or 1,1-bis(4-hydroxyphenyl)cyclohexane, etc.; biphenols such as 4,4'-dihydroxybiphenyl, or 3,3',5,5'-tetramethyl-4,4'-dihydroxybiphenyl; or bis(4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl) ether, or bis(4-hydroxyphenyl) ketone, etc. Among these, 2,2-bis(4-hydroxyphenyl)propane (i.e., bisphenol A) is preferred. These aromatic dihydroxy compounds can be used alone or in combination of two or more.

[0155] Specific examples of alicyclic dihydroxy compounds include 1,2-cyclohexanediethanol, 1,3-cyclohexanediethanol, 1,4-cyclohexanediethanol, tricyclodecanediethanol, pentacyclopentadecanedimethanol, 2,6-decahydronaphthalenediethanol, 1,5-decahydronaphthalenediethanol, 2,3-decahydronaphthalenediethanol, 2,3-norbornanediethanol, 2,5-norbornanediethanol, 1,3-adamantanediethanol, isosorbide, isomannitol, and iso-idylethanol. oidide), 3,9-bis(1,1-dimethyl-2-hydroxyethyl)-2,4,8,10-tetraoxazaspiro(5.5)undecane (common name: spirodiol), 3,9-bis(1,1-diethyl-2-hydroxyethyl)-2,4,8,10-tetraoxazaspiro(5.5)undecane, 3,9-bis(1,1-dipropyl-2-hydroxyethyl)-2,4,8,10-tetraoxazaspiro(5.5)undecane, or dioxanediol, etc.

[0156] <Transesterification Catalyst>

[0157] In transesterification reactions, transesterification catalysts can be used. Examples of transesterification catalysts include those used in the production of polycarbonate resins via transesterification, without particular limitation. Typically, examples include compounds of Group 1 (hereinafter referred to as "Group 1") elements (excluding hydrogen), compounds of Group 2 (hereinafter referred to as "Group 2") elements, basic boron compounds, basic phosphorus compounds, or basic ammonium compounds or amine compounds, etc.

[0158] Compounds containing Group 1 elements (excluding hydrogen) include inorganic compounds such as hydroxides, carbonates, or bicarbonates of Group 1 elements (excluding hydrogen); and organic compounds such as salts of Group 1 elements (excluding hydrogen) with alcohols, phenols, or organic carboxylic acids. Examples of Group 1 elements (excluding hydrogen) include lithium, sodium, potassium, rubidium, or cesium. Among these compounds containing Group 1 elements (excluding hydrogen), cesium compounds are preferred, and cesium carbonate, cesium bicarbonate, or cesium hydroxide are particularly preferred.

[0159] Compounds of Group 2 elements, for example, inorganic compounds such as hydroxides or carbonates of beryllium, magnesium, calcium, strontium, or barium; or salts of Group 2 elements with alcohols, phenols, or organic carboxylic acids.

[0160] Examples of basic boron compounds include sodium, potassium, lithium, calcium, magnesium, barium, and strontium salts. Examples of boron compounds include tetramethylboron, tetraethylboron, tetrapropylboron, tetrabutylboron, trimethylethylboron, trimethylbenzylboron, trimethylphenylboron, triethylmethylboron, triethylbenzylboron, triethylphenylboron, triethylbenzylboron, triethylphenylboron, tributylbenzylboron, tributylphenylboron, tetraphenylboron, benzyltriphenylboron, methyltriphenylboron, or butyltriphenylboron.

[0161] Examples of basic phosphorus compounds include trivalent phosphorus compounds such as triethylphosphine, tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine, triphenylphosphine, or tributylphosphine, or quaternary phosphorus salts derived from these compounds.

[0162] Examples of basic ammonium compounds 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, or butyltriphenylammonium hydroxide.

[0163] Examples of amine compounds include 4-aminopyridine, 2-aminopyridine, N,N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 2-hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 2-dimethylaminoimidazolium, 2-methoxyimidazolium, imidazolium, 2-mercaptoimidazolium, 2-methylimidazolium, or aminoquinoline.

[0164] In practical applications, at least one compound selected from the group consisting of compounds of Group 1 elements (excluding hydrogen) and compounds of Group 2 elements is preferred among these transesterification catalysts. These transesterification catalysts can be used alone or in combination of two or more.

[0165] The amount of transesterification catalyst used relative to 1 mole of aromatic dihydroxy compound is preferably 1 × 10⁻⁶. -9 ~1×10 -1 moles, more preferably 1 × 10 -7 ~1×10 -3 The mole, more preferably 1 × 10 -7 ~1×10 -5 Moore.

[0166] Transesterification catalysts are sometimes used as aqueous solutions. In this case, the concentration of the catalyst aqueous solution is not particularly limited and can be adjusted to any concentration based on the catalyst's solubility relative to water. Other solvents such as acetone, alcohols, toluene, or phenol can also be used instead of water.

[0167] Regarding the properties of the water used to dissolve the transesterification catalyst, there are no particular limitations as long as the types and concentrations of impurities it contains are constant. Distilled water or deionized water is generally preferred.

[0168] <Mixing ratio of diaryl carbonate to aromatic dihydroxy compounds>

[0169] As a method for manufacturing aromatic polycarbonate resin with the aforementioned suitable terminal hydroxyl concentration, methods for adjusting the mixing ratio of diaryl carbonate and aromatic dihydroxy compound for transesterification reaction can be cited. Specifically, it is preferable to use 1.03 times (molar ratio) or more of the diaryl carbonate relative to the aromatic dihydroxy compound, and more preferably 1.04 times (molar ratio) or more. By using the diaryl carbonate at or above the aforementioned lower limit, the terminal hydroxyl concentration of the obtained aromatic polycarbonate resin can be suppressed to below the aforementioned upper limit. The upper limit of the amount of diaryl carbonate used relative to the aromatic dihydroxy compound is preferably 1.30 times (molar ratio) or less, and more preferably 1.20 times (molar ratio) or less. By using the diaryl carbonate at or below the aforementioned upper limit, the transesterification reaction rate can be increased, and aromatic polycarbonate resin having the desired molecular weight can be manufactured efficiently. In addition, the amount of diaryl carbonate that may remain during the manufacture of aromatic polycarbonate resin can be reduced, and odor during molding processing and when the molded product is manufactured can be suppressed. However, the concentration of terminal hydroxyl groups in aromatic polycarbonate resins is determined not only by the mixing ratio of diaryl carbonate to aromatic dihydroxy compounds, but also by the shape of the apparatus and operating conditions. Therefore, it is preferable to measure the actual concentration of terminal hydroxyl groups in the aromatic polycarbonate resins obtained, and adjust the mixing ratio of diaryl carbonate to aromatic dihydroxy compounds accordingly based on the results.

[0170] <Polycondensation reaction treatment>

[0171] The feed mixture, prepared by mixing diaryl carbonate and aromatic dihydroxy compounds, is conveyed in a molten state to... Figure 1 The polycondensation reactor shown is a multi-stage apparatus utilizing multiple reactors connected in series for polycondensation reaction processing. The polycondensation reaction in this process is typically carried out continuously in two or more stages, preferably three to seven stages. Specific reaction conditions include, for example, temperature: 150–320°C, pressure: atmospheric pressure to 0.01 Torr (1.3 Pa), and average residence time: 5–150 minutes.

[0172] In the multi-stage process, in order to more effectively remove aromatic monohydroxy compounds such as phenol, which are byproducts of the polycondensation reaction, from the system, the reaction conditions are set to be progressively higher temperatures and higher vacuums. To prevent degradation of the color and other qualities of the obtained aromatic polycarbonate resin, it is preferable to set the temperature to be as low as possible and the residence time to be as short as possible.

[0173] In the case of multi-stage polycondensation treatment, multiple reactors, including vertical reactors, are typically set up to increase the average molecular weight of aromatic polycarbonate resins. Typically, 3 to 6 reactors are set up, preferably 4 to 5.

[0174] As an example, in Figure 1 In this process, three vertical reactors 11a-11c and one horizontal reactor 11d are connected in series. Molten feedstock mixture A is fed into the initial vertical reactor 11a, and the transesterification reaction begins in the presence of the aforementioned transesterification catalyst. Subsequently, it is sequentially fed to vertical reactors 11b, 11c, and 11d for further transesterification. Phenol is produced as a byproduct. The byproduct phenol is liquefied in a heat exchanger (condenser) 12 and sent to a phenol tank 13. The phenol in the phenol tank 13 is appropriately processed and reused as a feedstock such as aromatic dihydroxy compounds and diaryl carbonates.

[0175] As the final reactor in a series of polycondensation reaction units, the horizontal reactor 11d uses a horizontal (horizontal) axis of rotation for the stirring blades. This is because as the transesterification reaction proceeds, the viscosity increases, resulting in a high viscosity inside the reactor in the final stage, which makes stirring at this high viscosity easier.

[0176] Aromatic polycarbonate resin B obtained by polycondensation is discharged from horizontal reactor 11d, and cooled after devolatilization.

[0177] To remove the aforementioned volatile impurities as much as possible, the final reactor 11d is preferably set to high temperature and low pressure. Specifically, the temperature is preferably 275°C or higher, more preferably 280°C or higher. If the temperature is below 275°C, the residual amount of the aforementioned volatile impurities will increase, and the odor generated during melt molding may become stronger. The upper limit of the temperature is preferably 320°C or lower, more preferably 310°C or lower. If the temperature is above 320°C, the aromatic polycarbonate resin may sometimes turn yellow.

[0178] Furthermore, the pressure is preferably 100 Pa or less, more preferably 80 Pa or less. If the pressure is higher than 100 Pa, the residual amount of the aforementioned volatile impurities will increase, and the odor generated during melt forming may become stronger. There is no particular limitation on the lower limit of the pressure, but it is preferably 20 Pa or more, more preferably 30 Pa or more. The pressure can also be lower than 20 Pa, but the vacuum pump may sometimes be increased to the required level, increasing the driving power of the vacuum pump.

[0179] As vertical and horizontal reactors, such as stirred tank reactors, thin film reactors, centrifugal thin film evaporation reactors, surface-renewal biaxial mixing reactors, biaxial horizontal stirred reactors, wet-wall reactors, porous plate reactors that polymerize while falling freely, or porous plate reactors with metal wires that polymerize while falling along metal wires, etc.

[0180] Examples of the forms of stirring blades for vertical reactors include turbine blades, paddle blades, Pfaudler blades, anchor blades, fullzone blades (manufactured by Shinko Pantec Corporation), SANMELER blades (manufactured by Mitsubishi Heavy Industries Corporation), Maxblend blades (manufactured by Sumitomo Heavy Industries Corporation), ribbon blades, or torsion grid blades (manufactured by Hitachi, Ltd.).

[0181] Examples of stirring blades for horizontal reactors include single-shaft stirring blades such as circular plate type or paddle type, or bi-shaft stirring blades such as HVR, SCR, N-SCR (manufactured by Mitsubishi Heavy Industries, Ltd.), BIVOLAK (manufactured by Sumitomo Heavy Industries, Ltd.), spectacle-shaped blades, or grid-shaped blades (manufactured by Hitachi, Ltd.).

[0182] <Catalyst Deactivator>

[0183] In the reaction process, it is preferable to perform catalyst deactivation treatment by adding a catalyst deactivator after the transesterification reaction is completed. By adding this catalyst deactivator, further transesterification reactions can be inhibited, and the desired viscosity-average molecular weight can be obtained. In addition, the formation of aromatic monohydroxy compounds can be suppressed, and odor generation can be inhibited.

[0184] As a catalyst deactivator, there are no particular limitations on any compound that reduces the catalytic activity of transesterification catalysts, such as acidic compounds.

[0185] Specifically, examples include hydrochloric acid, nitric acid, boric acid, sulfuric acid, sulfurous acid, phosphoric acid, phosphorous acid, hypophosphoric acid, polyphosphoric acid, adipic acid, ascorbic acid, aspartic acid, azelaic acid, adenosine phosphate, benzoic acid, formic acid, isovaleric 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, nicotinic acid, picric acid, pyridinecarboxylic acid, phthalic acid, terephthalic acid, propionic acid, benzenesulfinic acid, benzenesulfonic acid, malonic acid, maleic acid, and other Brønsted acids, or their esters, acid halides, or salts. These can be used alone or in combination of two or more.

[0186] Among these acidic compounds, liquid sulfonic acids or their ester compounds that can be substituted with alkyl groups having 1 to 10 carbon atoms are preferred. Examples of sulfonic acids include benzenesulfonic acid, toluenesulfonic acid, or naphthalenesulfonic acid. Examples of ester compounds of sulfonic acids include methyl ester compounds, ethyl ester compounds, butyl ester compounds, octyl ester compounds, or phenyl ester compounds. Among these, butyl p-toluenesulfonate is particularly preferred.

[0187] The amount of catalyst deactivator added relative to 1 mole of transesterification catalyst is generally preferably 0.5 to 20 molar equivalents, more preferably 5 to 15 molar equivalents, and even more preferably in the range of 10 to 15 molar equivalents. If the amount of catalyst deactivator added is greater than 20 molar equivalents, the decrease in molecular weight may be greater when the molded article obtained by molding aromatic polycarbonate resin is exposed to high temperature and high humidity. As a result, the molded article may whiten or crack easily. If the amount of catalyst deactivator added is less than 0.5 molar equivalents, the molded article may yellow easily during the molding of aromatic polycarbonate resin. In addition, due to insufficient deactivation of the transesterification catalyst, transesterification reaction may occur in the process of adding heat stabilizers, release agents or colorants, in the process of forming particles, or during the molding of aromatic polycarbonate resin, generating aromatic monohydroxy compounds, and the odor of the molded article may become stronger.

[0188] Here, "molar equivalent" refers to the equivalent ratio of the transesterification catalyst to the active component of the catalyst. For example, in the case where the catalyst compound has two active catalyst metals, 1 molar equivalent relative to 1 mole of the catalyst is equivalent to 2 moles of catalyst deactivator.

[0189] <De-devouring process>

[0190] In the method for manufacturing aromatic polycarbonate resin, from the viewpoint of reducing the amount of the aforementioned non-volatile impurities containing low molecular weight products in the obtained aromatic polycarbonate resin, it is preferable to set up the following step: after the reaction step, specifically, for example after the transesterification reaction treatment (or, in the case where a polycondensation reaction treatment is also applied, a polycondensation reaction treatment), the reaction product is melt-blended and devolatilized using a twin-screw extruder with a vent.

[0191] The shafts of a twin-screw extruder with vents can rotate in different or the same direction; from the viewpoint of mixing performance, rotating in the same direction is preferred. By using a twin-screw extruder with vents rotating in the same direction, the supply of aromatic polycarbonate resin to the downstream filter can be stabilized.

[0192] As described above, non-volatile impurities that may adversely affect the product remain in the reaction product containing polycarbonate resin obtained from the transesterification reaction. These non-volatile impurities can be removed by using a twin-screw extruder with a vent, preferably by using a vacuum pump or similar device to reduce pressure at the vent. Alternatively, volatile liquids such as water can be introduced into the twin-screw extruder with the vent to promote volatilization. The twin-screw extruder with the vent can have one or more vents, preferably two or more.

[0193] In a twin-screw extruder with a vent, phosphorus compounds, hindered phenolic compounds, commonly known heat stabilizers, neutralizers, ultraviolet absorbers, light stabilizers, release agents, colorants, antistatic agents, lubricants, plasticizers, compatibilizers, flame retardants, or catalyst deactivators described above may be added and mixed.

[0194] The melt mixing temperature in a vented twin-screw extruder depends on the molecular weight of the aromatic polycarbonate resin, but the temperature of the aromatic polycarbonate resin at the outlet of the vented twin-screw extruder is preferably set to 275~350°C. If the melt mixing temperature at the extruder outlet is above the lower limit mentioned above, the melt viscosity of the aromatic polycarbonate resin can be reduced, the load on the extruder can be reduced, and the productivity can be increased. If the melt mixing temperature is below the upper limit mentioned above, the thermal degradation of the aromatic polycarbonate resin can be reduced, and adverse conditions such as reduced mechanical strength, coloring, and gas generation caused by the reduction of molecular weight can be suppressed.

[0195] After melt mixing and devolatilization using a twin-screw extruder with a vent, it is preferable to use a filter to remove foreign matter such as coking and gel from the aromatic polycarbonate resin.

[0196] Methods for melting and extruding aromatic polycarbonate resin using a twin-screw extruder with a vent, filtering it, cooling and curing it, and then granulating it include, for example, the following methods.

[0197] (1) Aromatic polycarbonate resin is fed from the final polycondensation reactor in a molten state to a twin-screw extruder with an exhaust port. After melt extrusion, it is filtered by a filter, cooled and solidified in the form of filaments, and granulated by a rotary cutter or the like.

[0198] (2) Aromatic polycarbonate resin is fed directly from the final polycondensation reactor in a molten state into a twin-screw extruder with an exhaust port. After melt extrusion, it is temporarily cooled and solidified into granules in the form of filaments. The granules are then introduced back into the extruder and melt extruded again. After filtration, they are cooled and solidified into granules in the form of filaments.

[0199] (3) Aromatic polycarbonate resin is taken out from the final polycondensation reactor in a molten state, cooled and solidified in the form of filaments without passing through an extruder, temporarily granulated, and then fed into a twin-screw extruder with a vent for melt extrusion. After being filtered, it is cooled and solidified in the form of filaments to form granules.

[0200] As the form of this filter, known filters such as candle filters, pleated filters, or disc filters can be used. Among them, disc filters are preferred because they have a larger filtration area relative to the housing container. It is preferable to use multiple filters in combination to obtain a larger filtration area.

[0201] The pore size of the filter is preferably 50 μm or less, more preferably 40 μm or less, based on a 99% filtration accuracy (absolute filtration accuracy). When it is desirable to particularly reduce foreign matter, the pore size of the filter is preferably 20 μm or less, and particularly preferably 10 μm or less. If the pore size becomes smaller, the pressure loss in the filter increases, which may lead to filter breakage or deterioration of the aromatic polycarbonate resin due to shear heating. Therefore, a pore size of 1 μm or more is preferred based on a 99% filtration accuracy. The pore size of the filter described above is the pore size determined according to ISO 16889.

[0202] [Polycarbonate resin composition]

[0203] Another embodiment of the polycarbonate resin composition of the present invention (also simply referred to as "polycarbonate resin composition") is a resin composition containing the above-described polycarbonate resin. This polycarbonate resin composition may also contain components other than the above-described polycarbonate resin (other components). This polycarbonate resin composition may be a solid or a liquid.

[0204] The content of polycarbonate resin in the polycarbonate resin composition is not particularly limited and can be appropriately set according to the application. It is usually 60% by mass or more, preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more. In addition, there is no particular limit to the upper limit of the content of polycarbonate resin, which can be 100% by mass or less.

[0205] <Content of aromatic monohydroxy compounds in polycarbonate resin compositions>

[0206] In the polycarbonate resin composition, the content of aromatic monohydroxy compounds (the content of aromatic monohydroxy compounds in the polycarbonate resin composition) is preferably 20 ppm by mass or less, particularly 18 ppm by mass or less, and especially 15 ppm by mass or less, relative to the polycarbonate resin composition. Aromatic monohydroxy compounds in the polycarbonate resin composition are the cause of odor during melt molding of the polycarbonate resin composition and the odor of the obtained molded article, and are preferably present in low amounts. There is no particular limitation on the lower limit of the content of aromatic monohydroxy compounds in the polycarbonate resin composition; it can be 0 ppm by mass (less than the detection limit) or more than 0 ppm by mass.

[0207] Methods for controlling the content of aromatic monohydroxy compounds in the polycarbonate resin composition within the aforementioned preferred range include, for example, adjusting the concentration of terminal hydroxyl groups in the polycarbonate resin, adjusting the amount of transesterification catalyst, or adjusting the amount of catalyst deactivation. That is, by reducing the concentration of terminal hydroxyl groups in the polycarbonate resin or the amount of transesterification catalyst, the rate of the transesterification reaction is reduced, resulting in a high vacuum in the final polymerization tank. This allows aromatic monohydroxy compounds to be efficiently removed from the system, thereby reducing the content of aromatic monohydroxy compounds in the polycarbonate resin composition. Furthermore, if the amount of catalyst deactivation is low, aromatic monohydroxy compounds are generated by conducting the transesterification reaction after the final polymerization tank, increasing the content of aromatic monohydroxy compounds in the polycarbonate resin. Therefore, the catalyst deactivation material is preferably selected from the preferred range described later.

[0208] The content of aromatic monohydroxy compounds in the polycarbonate resin was determined by the method described in one of the examples below.

[0209] <Content of other impurities in the polycarbonate resin composition>

[0210] The polycarbonate resin composition contains various non-volatile impurities that are byproducts of its manufacturing process. Examples of such volatile impurities include dicarbonate esters such as diphenyl carbonate used as raw materials for polycarbonate resin, unreacted raw materials such as dihydroxy compounds such as bisphenol A, and low molecular weight products. Examples of low molecular weight products include reaction byproducts such as phenol and the aforementioned aromatic monohydroxy compounds that are byproducts of polycondensation reactions (transesterification reactions).

[0211] The content of diaryl carbonate and other dicarbonate esters in the polycarbonate resin composition is preferably 120 ppm by mass or less, more preferably 110 ppm by mass or less, relative to the polycarbonate resin composition. If the content of diaryl carbonate is below the above-mentioned upper limit, the odor generated during melt molding can be suppressed. There is no particular limitation on the lower limit of the content of diaryl carbonate, which can be 0 ppm by mass (less than the detection limit) or more than 0 ppm by mass.

[0212] The content of these non-volatile impurities in the polycarbonate resin composition was determined by the method described in one of the examples below.

[0213] [Other Resins]

[0214] The polycarbonate resin composition may also contain resins other than the polycarbonate resins mentioned above (other resins). There are no particular limitations on the types of other resins, but examples include polycarbonate resins other than the polycarbonate resins mentioned above, polyacrylonitrile resins, polyethylene terephthalate resins, polybutylene terephthalate resins, polyethylene naphthalate resins, polyvinyl chloride resins, polyvinylidene chloride resins, polytrichloroethylene chloride resins, polyethylene resins, polypropylene resins, polystyrene resins, cyclic polyolefin resins, polynorbornene resins, polyethersulfone resins, polyetheretherketone resins, polyphenylene sulfide resins, polyarylate resins, polyamide resins, polyimide resins, triacetyl cellulose resins, polystyrene resins, epoxy resins, acrylic resins, or oxazine resins, etc.

[0215] <Solvent, Dispersion Medium>

[0216] The polycarbonate resin composition may also contain a solvent or a dispersion medium. There are no particular limitations on the type of solvent or dispersion medium; either a liquid capable of dissolving the components contained in the composition or a liquid capable of dispersing the components contained in the composition may be used.

[0217] <Additives for Polycarbonate Resin Compositions>

[0218] The polycarbonate resin composition may also contain components other than the polycarbonate resin and other resins described above (other components). An example of an additive that can be added to include such other components is described below.

[0219] Colorants can be added to polycarbonate resin compositions for coloring molded articles.

[0220] There are no particular limitations on the colorant, but in order to improve the odor caused by the dicarbonate that may be generated during the manufacture of polycarbonate resin, and to improve the hydrolysis and initial haze of the molded product, it is preferable to select one or more dye / pigment colorants from phthalocyanine blue and anthraquinone dyes.

[0221] Among phthalocyanine blues, Pigment Blue 15:3 (generic name in the colorant index) is preferred. Among anthraquinone dyes, blue or purple dyes are preferred. Particularly preferred are Solvent Blue 90, Solvent Blue 97, Solvent Violet 36, or Solvent Violet 13 (generic names in the colorant index, respectively). Of these, Pigment Blue 15:3 (generic name in the colorant index) is the most preferred.

[0222] Regarding the amount of colorant, there are no particular limitations as long as the molded article is colored to the desired hue. From the viewpoint of odor reduction, it is preferably 100 ppm by mass or less relative to the polycarbonate resin composition, more preferably 0.1 to 40 ppm by mass, and most preferably 5 to 30 ppm by mass. If the amount of colorant exceeds 100 ppm by mass, the odor reduction effect is small. The method and timing of adding the colorant to the polycarbonate resin composition are based on the method and timing of adding the additives described later.

[0223] The polycarbonate resin composition may be further formulated with at least one additive selected from stabilizers, UV absorbers, and release agents, as needed. There are no particular limitations on such additives; additives commonly used in polycarbonate resin compositions may be used.

[0224] Examples of stabilizers include hindered phenolic compounds, phosphorus compounds, sulfur compounds, epoxide compounds, or hindered amine compounds. Among these, at least one antioxidant selected from hindered phenolic compounds and phosphorus compounds is preferred.

[0225] Specific examples of hindered phenolic compounds include n-octadecyl-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate, 1,6-hexanediol-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], pentaerythritol-tetra[3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate], 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, triethylenediamine Alcohol-bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate] 3,5-di-tert-butyl-4-hydroxybenzyl phosphate-diethyl ester, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, 2,2-thio-diethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], tris-(3,5-di-tert-butyl-4-hydroxybenzyl)-isocyanurate, or N,N'-hexamethylenebis(3,5-di-tert-butyl-4-hydroxy-hydrogenated cinnamamide), etc. Among these, octadecyl-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate, 1,6-hexanediol-bis[3-(3',5'-tert-butyl-4'-hydroxyphenyl)propionate], or 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 are preferred.

[0226] The phosphorus compound is preferably a trivalent phosphorus compound. Particularly preferred are at least one selected from phosphites, which is a phosphite obtained by esterification of phenol and / or phenol having at least one alkyl group having 1 to 25 carbon atoms, and tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenyl diphosphonate.

[0227] Specific examples of phosphites include 4,4'-butylene-bis(3-methyl-6-tert-butylphenyl-di(tetrazyl))phosphite, 1,1,3-tris(2-methyl-4-di(tetrazyl)phosphite-5-tert-butylphenyl)butane, trinonylphenyl phosphite, dinonylphenyl pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl)phosphite, and bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite. Phosphites, such as di(2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, 2,2'-ethylidene-bis(4,6-di-tert-butylphenyl)fluorinated phosphite, 2,2'-methylene-bis(4,6-di-tert-butylphenyl)octyl phosphite, or bis(2,4-dicumylphenyl) pentaerythritol diphosphite, may also be phosphites containing monononylphenol, dinonylphenol, or hindered phenols.

[0228] As a phosphorus compound, tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenyl diphosphonate, or tris(2,4-di-tert-butylphenyl) phosphite, or 2,2'-methylene-bis(4,6-di-tert-butylphenyl) octyl phosphite are preferred.

[0229] The amount of stabilizer added is typically 1 part by weight or less, preferably 0.4 parts by weight or less, relative to 100 parts by weight of the polycarbonate resin composition. If the amount of stabilizer exceeds 1 part by weight, problems such as deterioration of hydrolysis resistance may occur. The ratio of stabilizer used can be arbitrarily determined, and the choice of which stabilizer to use or which to use in combination can be appropriately determined based on the intended use of the polycarbonate resin composition. Phosphorus compounds generally have high effects on retention stability at high temperatures during molding of the polycarbonate resin composition and on heat resistance stability when using the molded article. Hindered phenolic compounds generally have high effects on heat aging resistance and other heat resistance stability when the polycarbonate resin composition is molded. By using phosphorus compounds and hindered phenolic compounds in combination, the colorability is improved.

[0230] In addition to inorganic ultraviolet absorbers such as titanium dioxide, cerium oxide, or zinc oxide, organic ultraviolet absorbers such as benzotriazole compounds, benzophenone compounds, or triazine compounds can also be listed as ultraviolet absorbers. Among them, organic ultraviolet absorbers are preferred, and particularly preferred are at least one selected from benzotriazole compounds, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-(octyloxy)phenol, 2,2'-(1,4-phenylene)bis[4H-3,1-benzoxazin-4-one], and [(4-methoxyphenyl)-methylene]-dimethyl malonate.

[0231] Specific examples of benzotriazole compounds include 2-bis(5-methyl-2-hydroxyphenyl)benzotriazole, 2-(3,5-di-tert-butyl-2-hydroxyphenyl)benzotriazole, 2-(3',5'-di-tert-butyl-2'-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3-tert-butyl-5-methyl-2-hydroxyphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, and 2-(3,5'-di-tert-butyl-2'-hydroxyphenyl)benzotriazole. -Di-tert-pentyl-2-hydroxyphenyl)benzotriazole, 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-2H-benzotriazole, 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2N-benzotriazole-2-yl)phenol], or [methyl-3-[3-tert-butyl-5-(2H-benzotriazole-2-yl)-4-hydroxyphenyl]propionate-polyethylene glycol] condensate, etc.

[0232] Among these, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-2H-benzotriazole, 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2N-benzotriazole-2-yl)phenol], 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, or 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-(octyloxy)phenol are particularly preferred.

[0233] The amount of ultraviolet absorber incorporated is typically 10 parts by weight or less, preferably 1 part by weight or less, relative to 100 parts by weight of the polycarbonate resin composition. If the amount of ultraviolet absorber exceeds 10 parts by weight, problems such as mold contamination during injection molding may occur.

[0234] One type of ultraviolet absorber can be used, or multiple types can be used together.

[0235] As a release agent, at least one compound selected from aliphatic carboxylic acids, aliphatic carboxylic acid esters, aliphatic hydrocarbon compounds with a number average molecular weight of 200 to 15,000, and polysiloxane-based silicone oils can be used. Among these, at least one compound selected from aliphatic carboxylic acids and aliphatic carboxylic acid esters is preferred.

[0236] Examples of aliphatic carboxylic acids include saturated or unsaturated aliphatic monocarboxylic acids, dicarboxylic acids, and tricarboxylic acids. Aliphatic carboxylic acids also include alicyclic carboxylic acids. Preferred aliphatic carboxylic acids are monocarboxylic acids or dicarboxylic acids with 6 to 36 carbon atoms, and more preferably are saturated aliphatic monocarboxylic acids with 6 to 36 carbon atoms. Specific examples of aliphatic carboxylic acids include palmitic acid, stearic acid, isovaleric acid, hexanoic acid, decanoic acid, lauric acid, arachidic acid, docosanoic acid, tetracosanoic acid, ceric acid, beeswax acid, tritetracosanoic acid, linalool, glutaric acid, adipic acid, or azelaic acid.

[0237] As the aliphatic carboxylic acid component constituting the aliphatic carboxylic acid ester, the same aliphatic carboxylic acid as described above can be used. On the other hand, as the alcohol component constituting the aliphatic carboxylic acid ester, examples include saturated or unsaturated monohydric alcohols, or saturated or unsaturated polyhydric alcohols. These alcohols may also be substituted with fluorine atoms or aryl groups. Among these alcohols, monohydric or polyhydric saturated alcohols with 40 or fewer carbon atoms are preferred, and aliphatic saturated monohydric or polyhydric alcohols with 40 or fewer carbon atoms are more preferred. Here, aliphatic alcohols also include alicyclic alcohols.

[0238] Specific examples of these alcohols include octanol, decanol, dodecyl alcohol, stearyl alcohol, docosyl alcohol, ethylene glycol, diethylene glycol, glycerol, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentyl glycol, di(trimethylol)propane, or dipentaerythritol, etc.

[0239] Aliphatic carboxylic acid esters used as raw materials may contain aliphatic carboxylic acids and / or alcohols as impurities, or they may be mixtures of multiple compounds.

[0240] Specific examples of aliphatic carboxylic acid esters include beeswax (a mixture with myristyl palmitate as the main component), stearate, dodecyl dodecanoate, octyl dodecyl dodecanoate, glyceryl monopalmitate, glyceryl monostearate, glyceryl distearate, glyceryl tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, or pentaerythritol tetrastearate.

[0241] The amount of mold release agent added is typically 5 parts by weight or less, preferably 1 part by weight or less, relative to 100 parts by weight of the polycarbonate resin composition. If the amount of mold release agent added exceeds 5 parts by weight, problems such as reduced hydrolysis resistance and mold contamination during injection molding may occur.

[0242] One type of release agent can be used, or multiple types can be used together.

[0243] There are no particular restrictions on the timing and method of adding the aforementioned colorants, stabilizers, UV absorbers, or release agents.

[0244] For example, the additive can be added during (1) the transesterification reaction, (2) at the end of the transesterification reaction, or (3) after the catalyst used in the transesterification reaction has been deactivated by a catalyst deactivator and before granulation. It can also be added while the polycarbonate resin is molten, such as during the mixing of polycarbonate resin compositions. The additive can also be mixed with solid polycarbonate resin such as granules or powder and then compounded using an extruder or similar method.

[0245] However, from the viewpoint of inhibiting the decomposition of additives and inhibiting coloring, it is preferable to add additives at any stage, either during (1) the transesterification reaction, (2) at the end of the transesterification reaction, or (3) after the catalyst used in the transesterification reaction has been deactivated by a catalyst deactivator and before granulation.

[0246] As an addition method, additives such as colorants, stabilizers, UV absorbers, or release agents can be directly mixed or compounded into polycarbonate resin, or added as a high-concentration masterbatch prepared by dissolving in a suitable solvent or using a small amount of polycarbonate resin or other resins. When using these compounds together, they can be added separately to the polycarbonate resin composition or added simultaneously.

[0247] Without prejudice to the purpose of this invention, other thermoplastic resins, flame retardants, impact modifiers, antistatic agents, slip agents, anti-blocking agents, lubricants, anti-fogging agents, natural oils, synthetic oils, waxes, organic fillers, or inorganic fillers may be further added to the polycarbonate resin composition. That is, the polycarbonate resin composition can be used as a polycarbonate resin composition containing these additives.

[0248] <Method for manufacturing polycarbonate resin composition>

[0249] There are no particular limitations on the manufacturing method of the above-mentioned polycarbonate resin composition. For example, methods of mixing the required raw materials or methods of adding the required raw materials to a solvent or dispersion medium for mixing can be listed. As for the mixer used for mixing, examples include rotary drums, V-type mixers, Nauta mixers, Banbury mixers, mixing rollers, or extruders.

[0250] It should be noted that the polycarbonate resin composition may be the result of the polycarbonate resin manufacturing method described above (containing not only polycarbonate resin, but also impurities, etc.). Therefore, the description of the polycarbonate resin manufacturing method described above can also be treated as a description of the manufacturing method of the polycarbonate resin composition.

[0251] [Hollow container]

[0252] Another embodiment of the present invention is a hollow container, which is a blow-molded body obtained by blow molding the above-mentioned polycarbonate resin (in the present invention, it includes a polycarbonate resin composition containing polycarbonate resin).

[0253] In addition to direct blow molding, hollow containers can also be formed using injection blow molding or injection stretch blow molding, which are commonly known blow molding methods.

[0254] For example, in direct blow molding, polycarbonate resin granules are fed into a single-screw or twin-screw extruder with a barrel temperature set at 240-270°C. The granules are melted and mixed under screw shearing, and extruded through a nozzle to form a tubular molten preform. This preform is then clamped into a die with a predetermined shape and a temperature set at 70-110°C, and air or an inert gas is blown in to form a hollow container. It can also be formed using biaxial stretch blow molding as disclosed in Japanese Patent Application Publication No. 6-122140, etc. To improve the gas barrier properties of polycarbonate resin, it can also be formed by multilayer blow molding with polyethylene terephthalate and polyamide.

[0255] There is no particular limitation on the size of the hollow container obtained by blow molding of polycarbonate resin. From the viewpoint of maintaining the strength and shape of the hollow container, the wall thickness is preferably 0.1 to 7 mm, more preferably 0.2 to 5 mm, and most preferably 0.3 to 3 mm.

[0256] Hollow containers can be used for a wide variety of purposes, especially due to their low odor, making them suitable for dairy products, soft drink bottles, or water bottles, as well as other beverage or food containers, storage bottles, or transparent bottles.

[0257] [Sheet]

[0258] Another embodiment of the invention is a sheet material obtained by molding a polycarbonate resin (in this invention, including a polycarbonate resin composition containing polycarbonate resin).

[0259] It should be noted that, generally, "film" refers to a thin, flat product with a very small thickness compared to its length and width, and whose maximum thickness can be arbitrarily defined; it is usually supplied in roll form (JIS K6900). "Sheet" refers to a thin, flat product defined in JIS as having a thickness smaller than its length and width. However, the boundary between sheet and film is not clearly defined, and there is no need to distinguish between the two in the wording of this specification. Therefore, in this specification, the term "film" also includes "sheet," and vice versa.

[0260] There are no particular limitations on the manufacturing method of sheets made of polycarbonate resin. For example, sheets can be made by melt-blending polycarbonate resin with other resins and additives as needed through a single-screw or twin-screw extruder, extruding it into sheets through a T-die (metal nozzle), and then rapidly cooling and curing it with casting rolls.

[0261] In addition, sheets can be used as forming sheets for various secondary processing, and can also be thermoformed by heating. There are no particular limitations on the thermoforming method, and known forming methods such as foam forming, vacuum forming, or pneumatic forming can be used.

[0262] The thickness of the sheet is not particularly limited, but considering processability and practicality, it is preferably 0.01 mm or more and 5.0 mm or less, more preferably 0.03 mm or more and 3.0 mm or less, and even more preferably 0.05 to 1 mm. If the sheet thickness is within the above range, it is a preferred sheet material with excellent impact resistance and flexibility.

[0263] Due to its excellent heat resistance (hygrothermal stability), sheet material is not prone to problems such as whitening and cracking even when exposed to high temperature and high humidity conditions. Moreover, it has low odor, so it is suitable for use in food packaging materials, pharmaceutical packaging materials, agricultural sheet material, or building material sheet material.

[0264] Example

[0265] The present invention will be further described in detail below based on embodiments. The present invention is not limited to the following embodiments.

[0266] [Amount of methyl phenyl ester carbonate (MeDPC) in diphenyl carbonate]

[0267] 1.25 g of diphenyl carbonate was dissolved in acetonitrile and brought to a final volume of 25 mL. The solution was then analyzed by liquid chromatography under the following conditions to quantify methyl phenyl carbonate (MeDPC) in diphenyl carbonate.

[0268] Device: Shimadzu Corporation LC-20AD

[0269] Column: MCI GEL ODS-1HU 12cm × 4.6mm

[0270] Analysis temperature: 40℃

[0271] Composition of the eluent:

[0272] Liquid A pure water

[0273] B liquid acetonitrile

[0274] Gradient procedure:

[0275] During the analysis time of 0-60 minutes

[0276] Maintain the ratio of solution A to solution B at 50:50 (volume ratio, the same applies below).

[0277] Flow rate: 1.0 mL / min

[0278] Detection wavelength: 254nm

[0279] The concentration of methyl phenyl carbonate (MeDPC) in the solution was calculated based on a standard curve prepared from diphenyl carbonate, using the sum of the peak areas of o-MeDPC, m-MeDPC, and p-MeDPC. Based on this, the amount of MeDPC in diphenyl carbonate was calculated.

[0280] [Evaluation Method]

[0281] The properties of the polycarbonate resins obtained in the following examples and comparative examples were evaluated using the methods described below.

[0282] (1) Terminal hydroxyl concentration

[0283] The concentration of terminal hydroxyl groups obtained by colorimetric quantification was determined by using a colorimetric quantification method of titanium tetrachloride / acetic acid, and by the method described below.

[0284] (a) Preparation of 5 v / v% acetic acid solution

[0285] Add 50 mL of acetic acid to a 1000 mL volumetric flask, dilute to volume with dichloromethane and mix to prepare a 5 v / v% acetic acid solution.

[0286] (b) Preparation of titanium tetrachloride solution

[0287] In a 300 mL flask, add 90 mL of dichloromethane using a graduated cylinder, and add 10 mL of 5 v / v% acetic acid solution using a graduated cylinder. While adding a stir bar and stirring with a magnetic stirrer, slowly add 2.5 mL of titanium tetrachloride solution and 2.0 mL of methanol using a 5 mL graduated pipette to prepare the titanium tetrachloride solution.

[0288] (c) Modulation of standard curve samples

[0289] Prepare dichloromethane solutions by ensuring the terminal hydroxyl concentration of the dihydroxy compound in the raw material is 10 ppm by mass. Add 0 mL (no additive), 3 mL, or 5 mL to 25 mL volumetric flasks, respectively. Then, add 5 mL of 5 v / v% acetic acid and 10 mL of titanium tetrachloride solution, respectively. Make up to volume with dichloromethane and mix thoroughly to prepare standard curve samples.

[0290] (d) Construction of the standard curve

[0291] The absorbance of the prepared standard curve samples was measured at a detection wavelength of 546 nm. The obtained absorbance was plotted against the terminal hydroxyl concentration of the standard curve samples. The reciprocal of the slope was used as a factor.

[0292] (e) Determination of sample modulation and absorbance

[0293] 0.2 g of polycarbonate resin and 5 mL of dichloromethane were added to a 25 mL volumetric flask and dissolved. Then, 5 mL of 5 v / v acetic acid solution and 10 mL of titanium tetrachloride solution were added, and the mixture was brought to volume with dichloromethane and thoroughly mixed. The absorbance of the prepared solution was measured at a detection wavelength of 546 nm.

[0294] (f) Calculation of terminal hydroxyl concentration

[0295] The concentration of terminal hydroxyl groups in the polycarbonate resin is calculated by dividing the product of the measured absorbance and the factor by the concentration of the sample.

[0296] (2) Residual phenol content, diphenyl carbonate content, and bisphenol A content

[0297] 1.25 g of polycarbonate resin was dissolved in 7 mL of dichloromethane. While stirring, 30 mL of acetonitrile was added to the solution to allow it to precipitate again. The solution was then brought to a final volume of 50 mL with acetonitrile. The supernatant was analyzed by liquid chromatography under the following conditions to quantify the amount of residual phenol, diphenyl carbonate, and bisphenol A.

[0298] Device: Shimadzu Corporation LC-20AD

[0299] Column: SUPELCO Ascentis Express C18

[0300] 5cm×3.0mm, 2.7μm

[0301] Analysis temperature: 40℃

[0302] Composition of the eluent:

[0303] Solution A: 0.1% (w / w) phosphoric acid aqueous solution : acetonitrile = 5 : 1 (volume ratio)

[0304] B liquid acetonitrile

[0305] Gradient procedure:

[0306] At analysis time 0 minutes, the ratio of solution A to solution B is 97:3 (volume ratio, the same applies below).

[0307] The eluent composition was slowly changed to solution A:solution B = 55:45 during the analysis time of 0-6.5 minutes, and maintained at solution A:solution B = 2:98 during the analysis time of 7-14 minutes.

[0308] Flow rate: 1.0 mL / min

[0309] Detection wavelength: 210nm

[0310] The concentrations of phenol, diphenyl carbonate, and bisphenol A in the supernatant were calculated based on the peak areas of standard curves prepared from phenol, diphenyl carbonate, and bisphenol A, respectively. Based on this, the residual amounts of phenol, diphenyl carbonate, and bisphenol A in the polymer were calculated.

[0311] The detection location of each component is determined by the detection location of each standard curve.

[0312] (3) Viscosity-average molecular weight (Mv)

[0313] Polycarbonate resin was dissolved in dichloromethane (concentration 6.0 g / L), and the intrinsic viscosity (limiting viscosity) [η] (unit dL / g) at 20°C was determined using an Ubbelohde viscometer (manufactured by Moritomo Rika Co., Ltd.). The viscosity-average molecular weight (Mv) was then calculated according to Schnell's viscosity formula (the formula below).

[0314] η = 1.23 × 10 -4 Mv 0.83

[0315] (4) Specific by-product quantity

[0316] Dissolve 0.5g of polycarbonate resin in 5mL of dichloromethane, then add 45mL of methanol and 5mL of 25% sodium hydroxide aqueous solution. Stir at 70°C for 30 minutes to hydrolyze the solution (dichloromethane solution). Then, add 6 equivalents of hydrochloric acid to the dichloromethane solution to adjust the pH to approximately 2, and finally adjust the solution to 100mL with pure water.

[0317] Next, 20 μL of the prepared dichloromethane solution was injected into the liquid chromatograph, and the total content (unit: mass ppm) of the compounds represented by the above formulas (A) to (E) was determined as the content of specific byproducts.

[0318] The liquid chromatograph and measurement conditions are described below.

[0319] Liquid Chromatograph: LC-10AD manufactured by Shimadzu Corporation

[0320] Column: YMC PACK ODS-AM M-307-3

[0321] 4.6mm ID × 75mm L

[0322] Detector: UV280nm

[0323] Composition of the eluent:

[0324] Solution A is a 0.05% (w / w) trifluoroacetic acid aqueous solution.

[0325] B liquid methanol

[0326] Gradient procedure:

[0327] At analysis time 0 minutes, the ratio of solution A to solution B is 60:40 (volume ratio, the same applies below).

[0328] The eluent composition was slowly changed to solution A:solution B = 5:95 during the 0-25 minute analysis period, and maintained at solution A:solution B = 5:95 during the 25-30 minute analysis period.

[0329] The contents of the compounds represented by formulas (A) to (E) are calculated from their respective peak areas based on a standard curve prepared from bisphenol A.

[0330] (5) Amount of terminal groups (1)

[0331] Dissolve 0.5-1.0 g of polycarbonate resin in 5 mL of dichloromethane, then add 45 mL of methanol and 5 mL of 25% sodium hydroxide aqueous solution. Stir at 70°C for 30 minutes to hydrolyze the solution (dichloromethane solution). Then, add 6 equivalents of hydrochloric acid to the dichloromethane solution to adjust the pH to approximately 2, and finally adjust the solution to 100 mL with pure water.

[0332] Next, 20 μL of the prepared dichloromethane solution was injected into the liquid chromatograph, and the content of cresol was determined (unit: mass ppm).

[0333] The liquid chromatograph and measurement conditions are described below.

[0334] Liquid Chromatograph: LC-10AD manufactured by Shimadzu Corporation

[0335] Column: YMC PACK ODS-AM M-307-3

[0336] 4.6mm ID × 75mm L

[0337] Detector: UV280nm

[0338] Eluent:

[0339] Solution A is a 0.05% (w / w) trifluoroacetic acid aqueous solution.

[0340] B liquid methanol

[0341] Gradient procedure:

[0342] At analysis time 0 minutes, the ratio of solution A to solution B is 60:40 (volume ratio, the same applies below).

[0343] The eluent composition was slowly changed to solution A:solution B = 5:95 during the 0-25 minute analysis period, and maintained at solution A:solution B = 5:95 during the 25-30 minute analysis period.

[0344] The amount of cresol equivalent to the amount of terminal group (1) was calculated based on a standard curve made from o-cresol.

[0345] (6) Total number of terminal groups in the molecule, ratio of terminal groups (1) to all terminal groups

[0346] Dissolve 0.02 g of polycarbonate resin in 0.4 mL of deuterated chloroform and use at 30 °C. 1 H-NMR (JNM-Al400 manufactured by Nippon Electron Ltd.) was used to determine the amount of terminal hydroxyl groups (μeq / g) and the number of terminal phenyl groups (μeq / g). The two were added together to obtain the total number of terminal groups of the molecule. Then, based on the cresol content obtained from (5) above, the ratio of terminal groups (1) to all terminal groups was calculated using the following formula.

[0347] The ratio of terminal group (1) to all terminal groups =

[0348] {(cresol content (ppm) / cresol molecular weight) / total number of terminal molecules} × 100

[0349] (7) Total amount of aromatic terminal groups, ratio of terminal group (1) / total aromatic terminal groups

[0350] Dissolve 0.5-1.0 g of polycarbonate resin in 5 mL of dichloromethane, then add 45 mL of methanol and 5 mL of 25% sodium hydroxide aqueous solution. Stir at 70°C for 30 minutes to hydrolyze the solution (dichloromethane solution). Then, add 6 equivalents of hydrochloric acid to the dichloromethane solution to adjust the pH to approximately 2, and finally adjust the solution to 100 mL with pure water.

[0351] Next, 20 μL of the prepared dichloromethane solution was injected into the liquid chromatograph, and the amount of aromatic terminal groups other than the terminal group (1) of polycarbonate was determined (unit: mass ppm).

[0352] The liquid chromatograph and measurement conditions are described below.

[0353] Liquid Chromatograph: LC-10AD manufactured by Shimadzu Corporation

[0354] Column: YMC PACK ODS-AM M-307-3

[0355] 4.6mm ID × 75mm L

[0356] Detector: UV280nm

[0357] Eluent:

[0358] Solution A is a 0.05% (w / w) trifluoroacetic acid aqueous solution.

[0359] B liquid methanol

[0360] Gradient procedure:

[0361] At analysis time 0 minutes, the ratio of solution A to solution B is 60:40 (volume ratio, the same applies below).

[0362] During the analysis period of 0-25 minutes, the composition of the eluent was slowly changed to solution A:solution B = 5:95.

[0363] During the 25-30 minute analysis time, maintain the ratio of solution A:solution B = 5:95.

[0364] The phenol content, equivalent to the amount of aromatic terminal groups, is calculated based on a standard curve made from phenol.

[0365] The ratio of terminal group (1) to the total amount of aromatic terminal groups is calculated using the following formula based on the amount of aromatic terminal groups (mass ppm) and the amount of terminal group (1) (cresol content, mass ppm) obtained from (5) above.

[0366] The ratio of terminal group (1) to the total amount of aromatic terminal groups =

[0367] Amount of terminal groups (1) / (Amount of aromatic terminal groups + Amount of terminal groups (1))

[0368] (8) Molecular weight reduction rate and Δhaze after 100 hours at 120℃ and saturated water vapor.

[0369] The molecular weight reduction rate and Δhaze, measured at 120°C and under saturated water vapor for 100 hours, are determined to evaluate heat resistance (damp heat stability). Higher values ​​indicate worse heat resistance (damp heat stability).

[0370] For laboratory-scale test pieces (Examples 1, 2, 3, 4, 5, 6, Comparative Examples 1, 2, 3), polycarbonate resin granules were dried in a ventilated dryer at 120°C for 4 hours, and then injection molded using a small injection molding machine (SHINKOSELLBIC C, Mobile) to obtain plate-shaped molded bodies with a thickness of 3 mm, a length of 25 mm, and a width of 25 mm. The molding conditions were set as follows: barrel temperature 350°C and mold temperature 140°C (molding condition I).

[0371] For the test pieces at the actual machine scale (Examples 7, 8, and Comparative Example 4), polycarbonate resin particles were dried in a ventilated dryer at 120°C for 4 hours, and then injection molded using an injection molding machine (J75EII manufactured by Nippon Steel Co., Ltd.) at a mold temperature of 90°C to obtain a plate-shaped molded body with a thickness of 3 mm, a length of 60 mm, and a width of 60 mm. The molding conditions were set as follows: barrel temperature 280°C, molding cycle 37 seconds, and screw speed 90 rpm (molding condition II).

[0372] The obtained plate-shaped molded body was suspended in the gas phase and treated in an autoclave at 120°C and saturated vapor pressure for 100 hours.

[0373] The viscosity-average molecular weight (Mv) of the polycarbonate resin before and after treatment was determined by the above method, and the molecular weight reduction rate after treatment was calculated by the following formula.

[0374] Molecular weight reduction rate =

[0375] (Must-average molecular weight before treatment - Mutation-average molecular weight after treatment) / Mutation-average molecular weight before treatment × 100

[0376] In addition, for the plate-shaped molded bodies before and after treatment, according to JIS K7105 (1981), a haze meter (NDH2000 manufactured by Nippon Denshoku Kogyo Co., Ltd.) was used to measure the haze with a D65 light source, and the difference in haze values ​​before and after treatment was used to calculate Δhaze.

[0377] (9) Hue evaluation (grain YI)

[0378] According to ASTM D1925, the YI value (yellow index value) of polycarbonate resin particles in reflected light was determined and evaluated as follows. A Konica Minolta CM-5 spectrophotometer was used, with the measurement conditions selected as 30 mm measurement diameter and SCE.

[0379] The calibration glass CM-A212 for petri dish measurement was embedded into the measurement unit, and the zero calibration box CM-A124 was placed on top for zero calibration. Then, the built-in white calibration plate was used for white calibration. Measurements were performed using the white calibration plate CM-A210, confirming L* as 99.40±0.05, a* as 0.03±0.01, b* as -0.43±0.01, and YI as -0.58±0.01.

[0380] Regarding the YI value, the particles were filled into a cylindrical glass container with an inner diameter of 30 mm and a height of 50 mm to a depth of approximately 40 mm for measurement. After removing the particles from the glass container, the measurement was performed again, and this operation was repeated twice more. The average of the three measurements was used.

[0381] The smaller the YI value, the less yellow the resin has, which means a better hue.

[0382] [Abbreviated symbols]

[0383] The abbreviations for compounds, etc., used in the following examples and comparative examples are described below.

[0384] DPC: Diphenyl carbonate

[0385] BPA: Bisphenol A

[0386] MeDPC: Methylphenylphenyl carbonate

[0387] o-MeDPC: o-methylphenyl phenyl carbonate

[0388] PC: Polycarbonate resin

[0389] [Example 1]

[0390] 116.71 g (approximately 0.51 mol) of BPA, 117.29 g (approximately 0.55 mol) of DPC (with a MeDPC concentration of 70 ppm by mass) and 0.35 g of o-MeDPC were added to a 150 mL glass reactor equipped with a reactor stirrer, a reactor heating device, and a reactor pressure adjustment device. Cesium carbonate, used as a transesterification catalyst, was added to make it 0.5 μmol relative to 1 mol of BPA, and the mixture was prepared.

[0391] Next, the pressure inside the glass reactor was reduced to approximately 100 Pa (0.75 Torr), then restored to atmospheric pressure with nitrogen. This process was repeated three times to purge the reactor interior with nitrogen. After nitrogen purging, the external temperature of the reactor was set to 220°C, and the internal temperature was slowly increased to dissolve the mixture. Then, a stirrer was rotated at 100 rpm. The phenol, a byproduct of the oligomerization reaction of BPA and DPC occurring inside the reactor, was then distilled off while the pressure inside the reactor was reduced from 101.3 kPa (760 Torr) to 13.3 kPa (100 Torr) using an absolute pressure gauge over 40 minutes.

[0392] Next, the pressure inside the reactor was maintained at 13.3 kPa, and an ester exchange reaction was carried out for 80 minutes while further distilling away the phenol. Then, the external temperature of the reactor was raised to 290°C, and the pressure inside the reactor was reduced from 13.3 kPa (100 Torr) to 399 Pa (3 Torr) using an absolute pressure gauge over 40 minutes to remove the distilled phenol from the system. The absolute pressure inside the reactor was further reduced to 30 Pa (approximately 0.2 Torr) to carry out a polycondensation reaction. The polycondensation reaction was terminated when the reactor agitator reached the predetermined stirring power.

[0393] Next, after the pressure inside the reactor was restored to 101.3 kPa using an absolute pressure gauge with nitrogen, butyl p-toluenesulfonate was added as a catalyst deactivator at a concentration of 5 ppm by mass. After stirring for 10 minutes, the pressure was increased to 0.2 MPa using a gauge pressure gauge with nitrogen. The polycarbonate resin was then removed from the reactor in the form of a filament. After obtaining the filament polycarbonate resin, it was granulated using a rotary cutter.

[0394] The evaluation results of the obtained polycarbonate resins are shown in Table 1.

[0395] [Examples 2, 3, 4, 5, 6, Comparative Examples 1, 2, 3]

[0396] As shown in Table 1, the polycarbonate resins were obtained by varying the amounts of o-MeDPC and DPC, otherwise following the same procedure as in Example 1. The evaluation results of the obtained polycarbonate resins are shown in Table 1.

[0397] [Example 7]

[0398] Under a nitrogen atmosphere, a molten mixture of BPA and DPC (MeDPC concentration: 100 ppm) at a specific molar ratio (DPC / BPA molar ratio = 1.070) is continuously fed through a feed inlet pipe to a controlled temperature of 13.3 × 10⁻⁶ ppm. 3 In the first vertical reactor at 220°C and Pa, the valve opening of the polymer discharge line located at the bottom of the reactor is controlled to maintain an average residence time of 60 minutes, while simultaneously keeping the liquid level constant. Additionally, at the start of the above-mentioned raw material supply, the amount of cesium carbonate relative to 1 mole of BPA is 0.6 × 10⁻⁶. -6 A cesium carbonate aqueous solution, used as a catalyst, is continuously supplied at a flow rate of 0.6 μmol / 1 mol BPA. The generated distillates, such as phenol, are continuously liquefied and recovered via a heat exchanger located in the distillation line of the first vertical reactor. The reaction liquid discharged from the first vertical reactor is then successively introduced into the second, third, and fourth horizontal reactors.

[0399] The operating conditions of each reactor are as follows, and as the reaction proceeds, the temperature and vacuum become higher.

[0400] Second vertical reactor: 260℃, 4.00×10 3 Pa, 75 rpm

[0401] Third vertical reactor: 270℃, 200Pa, 75rpm

[0402] Fourth horizontal reactor: outlet resin temperature 288℃, 75Pa, 4rpm

[0403] In addition, during the reaction, the liquid level was controlled so that the average residence time of the second and third vertical reactors was 60 minutes and the average residence time of the fourth horizontal reactor was 90 minutes, while the by-product phenol was removed by distillation.

[0404] Next, the polymer melt taken from the fourth horizontal reactor is introduced into a twin-screw extruder with three venting ports and three feeding ports (screw diameter 46mm, partially meshing screw type, rotating in the same direction). The butyl p-toluenesulfonate as a catalyst deactivator and tris(2,4-di-tert-butylphenyl) phosphate as a heat stabilizer are supplied at 5 ppm by mass and 100 ppm by mass relative to the polycarbonate resin, respectively. After devolatilization at each venting port (exit temperature of the twin-screw extruder with venting ports: 330°C), the mixture is filtered using a disc-type polymer filter (made by mounting 135 discs made of woven gold mesh with an absolute filtration accuracy of 40μm on a central column), and then water-cooled and granulated.

[0405] The evaluation results of the obtained polycarbonate resins are shown in Table 2.

[0406] [Example 8, Comparative Example 4]

[0407] As shown in Table 2, the MeDPC concentration, DPC / BPA molar ratio, catalyst amount, resin outlet temperature of the fourth horizontal reactor, vacuum degree inside the fourth horizontal reactor, and catalyst deactivator addition were varied, but the process was otherwise the same as in Example 7. The evaluation results of the obtained polycarbonate resin are shown in Table 2.

[0408] For Examples 1-8 and Comparative Examples 1-4, the polycarbonate resin in any example has only o-cresol end groups (1), and no other end groups (1) besides o-cresol end groups are present.

[0409] [Table 1]

[0410]

[0411] [Table 2]

[0412]

[0413] According to Tables 1 and 2, polycarbonate resins with a terminal group (1) / total terminal group ratio in the range of 0.024 to 4.0 mol% have lower odor due to less residual phenol, BPA and DPC and other non-volatile impurities. In addition, after being treated at 120°C and saturated water vapor for 100 hours, the Δ haze and molecular weight reduction rate are small, and the heat resistance (damp heat stability) is also excellent.

[0414] In contrast, Comparative Examples 1, 2, and 4, where the ratio of terminal group (1) to all terminal groups is less than 0.024 mol%, and Comparative Example 3, where the ratio of terminal group (1) to all terminal groups is more than 4.0 mol%, have high levels of residual phenol, residual BPA, and residual DPC, resulting in odor problems. In addition, their heat resistance (damp heat stability) is also poor.

[0415] The invention has been described in detail using specific methods, but it will be apparent to those skilled in the art that various modifications can be made without departing from the intent and scope of the invention.

[0416] Symbol Explanation

[0417] Vertical reactors 11a, 11b, and 11c

[0418] 11d horizontal reactor

[0419] 12 heat exchangers

[0420] 13 Phenol Cans

[0421] A raw material mixture

[0422] B. Aromatic polycarbonate resin.

Claims

1. A hollow container, which is a blow-molded polycarbonate resin having terminal groups represented by formula (1) below, wherein the proportion of the terminal groups represented by formula (1) below to the total number of terminal groups of the polycarbonate resin is 0.024 to 1.338 mol%. In the above formula (1), X 1 ~X 5 They can be the same or different, each independently representing an alkyl group with 1 to 3 hydrogen atoms or carbon atoms, wherein, X in equation (1) 1 ~X 5 At least one of them is an alkyl group having 1 to 3 carbon atoms, and * indicates a bond with the polycarbonate resin chain. The polycarbonate resin has a viscosity-average molecular weight of 14,000 or more and 30,000 or less. The concentration of terminal hydroxyl groups in the polycarbonate resin is above 100 ppm by mass and below 1000 ppm by mass.

2. A hollow container, which is a blow-molded body of a polycarbonate resin composition containing polycarbonate resin, said polycarbonate resin having terminal groups represented by the following formula (1), wherein the proportion of the terminal groups represented by the following formula (1) to all terminal groups is 0.024 to 4.0 mol%, and the proportion of the terminal groups represented by the following formula (1) to all terminal groups of said polycarbonate resin is 0.030 to 2.0 mol%. In the above formula (1), X 1 ~X 5 They can be the same or different, each independently representing an alkyl group with 1 to 3 hydrogen atoms or carbon atoms, wherein, X in equation (1) 1 ~X 5 At least one of them is an alkyl group having 1 to 3 carbon atoms, and * indicates a bond with the polycarbonate resin chain.

3. The hollow container according to claim 1 or 2 is a dairy product bottle, a soft drink bottle, or a water bottle.

4. The hollow container according to claim 1 or 2, wherein the terminal group represented by formula (1) is methylphenoxy.

5. The hollow container according to claim 1 or 2, wherein the polycarbonate resin is an ester exchange product of a dihydroxy compound and a diester, the dihydroxy compound comprising at least one selected from the group consisting of aromatic dihydroxy compounds, aliphatic dihydroxy compounds and alicyclic dihydroxy compounds.

6. The hollow container according to claim 5, wherein the aromatic dihydroxy compound is bisphenol A.

7. The hollow container according to claim 1 or 2, wherein the total amount of compounds represented by formulas (A) to (E) in the hydrolysate obtained by hydrolyzing the polycarbonate resin is 500 to 6,000 ppm by mass relative to the polycarbonate resin. R in the above formula (A) 1 R in equation (B) 2 R in equation (C) 3 R 4 R in formula (D) 5 R 6 Each can be used independently to represent a hydrogen atom or a methyl group.

8. The hollow container according to claim 7, wherein the total amount of the compounds represented by formulas (A) to (E) in the hydrolysate obtained by hydrolyzing the polycarbonate resin is 2,000 to 6,000 ppm by mass relative to the polycarbonate resin.

9. The hollow container according to claim 7, wherein the total amount of the compounds represented by formulas (A) to (E) obtained by hydrolyzing the polycarbonate resin is 3,000 to 6,000 ppm by mass relative to the polycarbonate resin.

10. The hollow container according to claim 1 or 2, wherein the concentration of terminal hydroxyl groups in the polycarbonate resin is below 700 ppm by mass.

11. The hollow container according to claim 1 or 2, characterized in that, The total amount of the compound represented by the following formula (2) in the hydrolysate obtained by hydrolyzing the polycarbonate resin is 4 to 1,500 ppm by mass relative to the polycarbonate resin. In equation (2) above, X 1 ~X 5 respectively with X in the above formula (1) 1 ~X 5 Synonyms.

12. The hollow container according to claim 1 or 2, wherein the molded body obtained by molding the polycarbonate resin under the following molding conditions I has a Δhaze of 4.3 or less after 100 hours at 120°C and saturated water vapor. Forming conditions I: After the polycarbonate resin particles are dried at 120°C for 4 hours, they are injection molded using an injection molding machine at a barrel temperature of 350°C and a mold temperature of 140°C to obtain a plate-shaped molded body with a thickness of 3mm, a length of 25mm, and a width of 25mm.

13. The hollow container according to claim 2, wherein the content of aromatic monohydroxy compounds in the polycarbonate resin composition is less than 20 ppm by mass.

14. A method for manufacturing polycarbonate resin, characterized in that, include: The process of obtaining polycarbonate resin involves an transesterification reaction in which a dihydroxy compound is exchanged with a diester. The polycarbonate resin has terminal groups represented by the following formula (1), wherein the proportion of the terminal groups represented by the following formula (1) to the total number of terminal groups of the polycarbonate resin is 0.024~1.338 mol%. In the above formula (1), X 1 ~X 5 They can be the same or different, each independently representing an alkyl group with 1 to 3 hydrogen atoms or carbon atoms, wherein X in formula (1) 1 ~X 5 At least one of them is an alkyl group having 1 to 3 carbon atoms, and * indicates a bond with the polycarbonate resin chain. The polycarbonate resin has a viscosity-average molecular weight of 14,000 or more and 30,000 or less. The concentration of terminal hydroxyl groups in the polycarbonate resin is above 100 ppm by mass and below 1000 ppm by mass. The carbonate diester comprises the carbonate diester represented by the following formula (3), In the above formula (3), X 1A ~X 5A and X 1B ~X 5B They can be the same or different, each independently representing an alkyl group with 1 to 3 hydrogen atoms or carbon atoms, wherein X in formula (3) 1A ~X 5A and X 1B ~X 5B At least one of them is an alkyl group having 1 to 3 carbon atoms.

15. The method for manufacturing polycarbonate resin according to claim 14, characterized in that, The carbonate diester further comprises diphenyl carbonate, and the ratio of the amount of the carbonate diester represented by formula (3) to the amount of the diphenyl carbonate is 80 to 35,000 ppm by mass.

16. The method for manufacturing polycarbonate resin according to claim 14, characterized in that, The carbonate diester represented by formula (3) is methyl phenyl phenyl carbonate.

17. The method for manufacturing polycarbonate resin according to claim 14, characterized in that, The dihydroxy compound comprises at least one selected from the group consisting of aromatic dihydroxy compounds, aliphatic dihydroxy compounds, and alicyclic dihydroxy compounds.

18. The method for manufacturing polycarbonate resin according to claim 17, characterized in that, The dihydroxy compound is bisphenol A.

19. The method for manufacturing polycarbonate resin according to claim 14, characterized in that, Further includes: The process following the reaction step involves using a twin-screw extruder with a vent to perform a devolatilization of the polycarbonate resin.

20. The method for manufacturing polycarbonate resin according to claim 14, characterized in that, In the reaction process, The reaction was carried out in the presence of an transesterification catalyst. After the reaction treatment, a further catalyst deactivation treatment is carried out by adding 5 to 15 molar equivalents of catalyst deactivator relative to 1 mole of the transesterification catalyst.

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