Abstract: The invention is to provide polycarbonate resins having excellent light resistance, transparency, hue, heat resistance, thermal stability, and mechanical strength and to provide processes for efficiently and stably producing a polycarbonate resin which stably shows those performances. The invention includes: polycarbonate resins which at least contain structural units derived from a dihydroxy compound having the portion represented by the following general formula (1) as part of the structure thereof and which have specific properties; and processes for producing the polycarbonate resins. [Chem. 1] CH2—O??(1) (The case where the portion represented by general formula (1) is part of —CH2—O—H is excluded.

Abstract: The present invention relates to a transparent film obtained by molding a polycarbonate resin composition comprising a specific weight of (A) a polycarbonate resin containing (a) a specific structural unit and (b) a specific structural unit, and a specific weight of (B) a resin having a composition different from that of the polycarbonate resin (A), with a specific absolute value of the difference in the glass transition temperature between the resin (B) and the polycarbonate resin (A) and a specific absolute value of the difference in the refractive index, wherein in the transparent film, the ratio of the retardation measured at a wavelength of 450 nm to the retardation measured at a wavelength of 550 nm satisfies a specific formula.

Abstract: The present invention provides a long retardation film having sufficient reversed wavelength dispersion characteristics and favorable for film lamination according to a roll-to-roll system. A long retardation film of the present invention includes a polycarbonate resin or a polyester carbonate resin, an orientation angle ? which is an angle between a slow axis and a width direction satisfies the following formula (I), and a ratio of an in-plane retardation R450 measured at a wavelength of 450 nm to an in-plane retardation R550 measured at a wavelength of 550 nm satisfies the following formula (II): 38°???52°??(I) R450/R550<1??(II).

Abstract: The polycarbonate resin of the present invention comprises a structural unit derived from a dihydroxy compound represented by a specific formula (1), a structural unit derived from a dihydroxy compound represented by a specific formula (2), and a structural unit derived from a dihydroxy compound represented by any one of specific formulae (3) to (6), wherein the content of structural units derived from dihydroxy compounds represented by the specific formulae (3) to (6) is within a specific range based on the total of structural units derived from dihydroxy compounds in the polycarbonate resin.

Abstract: The polycarbonate resin of the present invention comprises a structural unit derived from a dihydroxy compound represented by a specific formula (1), a structural unit derived from a dihydroxy compound represented by a specific formula (2), and a structural unit derived from a dihydroxy compound represented by any one of specific formulae (3) to (6), wherein the content of structural units derived from dihydroxy compounds represented by the specific formulae (3) to (6) is within a specific range based on the total of structural units derived from dihydroxy compounds in the polycarbonate resin.

Abstract: The present invention is a production method of a polycarbonate resin, including a step of performing melt polycondensation by continuously feeding a dihydroxy compound (A) having a predetermined moiety in a part of the structure and a carbonic acid diester each in a liquid state to a reactor, wherein the residence time from liquefaction of the dihydroxy compound to its feeding to a reactor is from 0.1 to 10 hours.

Abstract: The present invention is a production method of a polycarbonate resin, including a step of performing melt polycondensation by continuously feeding a dihydroxy compound (A) having a predetermined moiety in a part of the structure and a carbonic acid diester each in a liquid state to a reactor, wherein the residence time from liquefaction of the dihydroxy compound to its feeding to a reactor is from 0.1 to 10 hours.

Abstract: A retardation film insusceptible to color dropout or color shift even under environment of severe temperature or humidity conditions and capable of being produced by a melt film-forming method. The retardation film is obtained by molding at least one polymer selected from polycarbonate and polyester carbonate each having a glass transition temperature of 110 to 180° C. and satisfies the relationships of the following formulae (A) and (B): 0.7<R1(450)/R1(550)<1??Formula (A): |R2(450)/R2(550)?R1(450)/R1(550)|<0.020.

Abstract: The present invention relates to a method for producing a polycarbonate having excellent characteristics such as hue and mechanical properties with a stable quality and a high yield by solving a plurality of problems as those described above in producing a polycarbonate by using a specific dihydroxy compound exhibiting low thermal stability as compared with bisphenols and having a —CH2—O— structure. The polycarbonate obtained by polycondensation in the present invention is a polycarbonate having an appropriate viscosity despite decrease in the reaction temperature, providing for a color tone less susceptible to yellowing, and exhibiting excellent mechanical properties.

Abstract: A method for producing a polycarbonate resin comprises a step of performing polycondensation through a transesterification reaction in the presence of a transesterification catalyst by using a dihydroxy compound as a raw material compound and a carbonic acid diester, wherein the dihydroxy compound comprises at least an aliphatic dihydroxy compound having an etheric oxygen atom on a hydroxy group, the raw material compound comprises the specific amount of a nitrogen-containing compound, and the production method of a polycarbonate resin comprises a step of previously heating the aliphatic dihydroxy compound at the specific temperature, holding the compound in the melted state for the specific time, and then mixing the melt with a carbonic acid diester.

Abstract: The invention is to provide polycarbonate resins having excellent light resistance, transparency, hue, heat resistance, thermal stability, and mechanical strength and to provide processes for efficiently and stably producing a polycarbonate resin which stably shows those performances. The invention includes: polycarbonate resins which at least contain structural units derived from a dihydroxy compound having the portion represented by formula (1) as part of the structure thereof and which have specific properties; and processes for producing the polycarbonate resins, ?CH2—O???(1) where the case where the portion represented by formula (1) is part of —CH2—O—H is excluded.

Abstract: The polycarbonate resin of the present invention comprises a structural unit derived from a dihydroxy compound represented by a specific formula (1), a structural unit derived from a dihydroxy compound represented by a specific formula (2), and a structural unit derived from a dihydroxy compound represented by any one of specific formulae (3) to (6), wherein the content of structural units derived from dihydroxy compounds represented by the specific formulae (3) to (6) is within a specific range based on the total of structural units derived from dihydroxy compounds in the polycarbonate resin.

Abstract: The present invention relates to a method for producing a polycarbonate having excellent characteristics such as hue and mechanical properties with a stable quality and a high yield by solving a plurality of problems as those described above in producing a polycarbonate by using a specific dihydroxy compound exhibiting low thermal stability as compared with bisphenols and having a —CH2—O— structure. The polycarbonate obtained by polycondensation in the present invention is a polycarbonate having an appropriate viscosity despite decrease in the reaction temperature, providing for a color tone less susceptible to yellowing, and exhibiting excellent mechanical properties.

Abstract: The present invention is a production method of a polycarbonate resin, including a step of performing melt polycondensation by continuously feeding a dihydroxy compound (A) having a predetermined moiety in a part of the structure and a carbonic acid diester each in a liquid state to a reactor, wherein the residence time from liquefaction of the dihydroxy compound to its feeding to a reactor is from 0.1 to 10 hours.

Abstract: The present invention is a method for producing a polycarbonate resin, comprising performing polycondensation through a transesterification reaction by using a catalyst and using a dihydroxy compound and a carbonic acid diester as raw material monomers, and feeding the produced polycarbonate resin to an extruder, wherein the dihydroxy compound contains at least a dihydroxy compound having a moiety represented by formula (1) in a part of the structure, the dihydroxy compound having a moiety represented by formula (1) contains a compound having a cyclic ether structure, and the temperature at the time of feeding the polycarbonate resin to the extruder is from 180° C. to less than 250° C., with the proviso excluding the case where the moiety represented by formula (1) is a part of —CH2—O—H.

Abstract: A method for producing a polycarbonate resin comprises a step of performing polycondensation through a transesterification reaction in the presence of a transesterification catalyst by using a dihydroxy compound as a raw material compound and a carbonic acid diester, wherein the dihydroxy compound comprises at least an aliphatic dihydroxy compound having an etheric oxygen atom on a hydroxy group, the raw material compound comprises the specific amount of a nitrogen-containing compound, and the production method of a polycarbonate resin comprises a step of previously heating the aliphatic dihydroxy compound at the specific temperature, holding the compound in the melted state for the specific time, and then mixing the melt with a carbonic acid diester.

Abstract: A method for producing a polycarbonate, comprises: continuously feeding a dihydroxy compound having a portion represented by —(—CH2—O—)— in a part of a structure thereof and a carbonic acid diester; and continuously performing polycondensation to produce a polycarbonate, wherein the method satisfies all of the conditions: (A) at least two reactor vessels connected in series are used; (B) a reaction solution reacted in a first reactor of the first vessel is continuously fed to a reactor of the second vessel; (C) the first reactor is equipped with a reflux condenser; and (D) a reflux ratio in the first reactor is from 0.01 to 10 based on a distillate volume.

Abstract: A method for producing a polycarbonate, comprises: continuously feeding a dihydroxy compound having a portion represented by —(—CH2—O—)— in a part of a structure thereof and a carbonic acid diester; and continuously performing polycondensation to produce a polycarbonate, wherein the method satisfies all of the conditions: (A) at least two reactor vessels connected in series are used; (B) a reaction solution reacted in a first reactor of the first vessel is continuously fed to a reactor of the second vessel; (C) the first reactor is equipped with a reflux condenser; and (D) a reflux ratio in the first reactor is from 0.01 to 10 based on a distillate volume.

Abstract: A polycarbonate resin which is excellent in terms of optical properties, hue, thermal stability, and mechanical properties and a transparent film formed from the resin are provided. The invention relates to a polycarbonate resin which has a glass transition temperature of 110-150° C. and a reduced viscosity, as measured at 20° C. with respect to the methylene chloride solution having a concentration of 0.6 g/dL, of 0.30-0.46, and which, when being molded, gives a film wherein the ratio of the retardation thereof measured at a wavelength of 450 nm (Re450) to the retardation thereof measured at a wavelength of 550 nm (Re550) is 0.50-0.93.

Abstract: A subject for the invention is to provide a polycarbonate having excellent mechanical strength, heat resistance, a low refractive index, a large Abbe number, reduced birefringence, and excellent transparency. The invention relates to a polycarbonate characterized by being obtained by subjecting one or more dihydroxy compounds including a dihydroxy compound having at least one linking group —CH2—O— in the molecule thereof to melt polycondensation with a carbonic acid diester, and by having a reduced viscosity of from 0.40 dL/g to 1.70 dL/g and a formic acid content lower than 5 ppm by weight.