摘要:
The invention provides a process for the preparation of polycarbonate by the melt transesterification process, polycarbonate having a low electrostatic charge obtainable by this process, and mouldings or extrudates, in particular optical data storage media or light-diffusing plates, made from this polycarbonate.
摘要:
The invention relates to a process for the preparation of polycarbonate by the melt transesterification method, polycarbonate having a small buildup of electrostatic charge and obtainable by this process and shaped articles or extrudates, in particular optical data stores or diffuser discs, comprising this polycarbonate.
摘要:
A process for purifying polycarbonate is disclosed. The process entails filtering molten polycarbonate having weight average molecular weight of 14,000 to 30,000 g/mol through at least one non-woven metal structure having a thickness of 5 to 1 mm, said structure including at least one dense layer, and at least one less dense layer wherein said dense layer is 0.05 to 0.2 mm thick and has pore size of 1 to 10 μm to obtain pure polycarbonate.
摘要:
An improvement to the phase interface process of preparing aromatic polycarbonate is disclosed. The process is characterized in that the phosgenation is carried out at 0 to 40° C., and in that the temperature of the reaction mixture at the time of addition of the catalyst at 10 to 40° C., and in that the molar ratio of aromatic dihydroxy compounds to phosgene at 1:1.05 to 1:1.20. The polycarbonate thus produced is characterized in its low content of carbamates, making it particularly suitable for the preparation of optical storage media.
摘要:
A polycarbonate resin comprising fluorescing particles that feature a particular size distribution is disclosed. The size distribution of these particles that fluoresce upon excitation at wavelengths of 400-440 nm, 50× magnification and illumination time of 40 msec per scan was found to be critical in determining the suitability of the resin for optical, particularly optical storage, applications.
摘要:
A polymeric material suitable for making a substrate for optical data storage disks is disclosed. The material, preferably aromatic polycarbonate is characterized in that the potential on 95 to 100% of the total surface of a disk molded therefrom is from −1.5 to +1.5 kV, and in that the potential on 0 to 5% of the total surface of said disk is between −1.5 and −2.5, and +1.5 to +2.5, and in that the potential on no more than 1% of the total surface of said disk is less than −2.5 kV and more than +2.5 kV. The potential measurements are carried out by means of a Monroe probe at a distance of 3.5 mm from the surface of the disk, the scanning region is in each case 12 cm in the X- and Y-direction, and in each case in steps of 2 mm in the X- and in the Y-directions.
摘要:
A substrate material, preferably polycarbonate, suitable for producing transparent injection-molded coated disks is disclosed. The material is characterized in that a substrate molded therefrom has an electrical field (measured within 5 minutes of its molding and at a distance of 100 mm from the surface) of −30 to 0 kV/m.
摘要:
This invention relates to an optical recording medium in which at least a recording layer and a light transmitting layer are sequentially formed on a substrate and in which the light is illuminated from the light transmitting layer side for recording and/or reproducing information signals, said substrate comprising an injection molded part, and said substrate having a Young's modulus E of at least 2.15 GPa and a Q factor of lower than 160 measured at 25° C. at 2000 Hz in accordance to ASTM E 756-05 05 and a transcriptability of the pit/groove structure of >85%.
摘要翻译:本发明涉及一种光记录介质,其中至少记录层和透光层依次形成在基板上,并且其中光从光透射层侧照射以用于记录和/或再现信息信号,所述基板 包括注塑部件,并且所述基材根据ASTM E 756-05 05在2000Hz下在25℃下测量的杨氏模量E为至少2.15GPa和低于160的Q因子,并且其转录率 坑/槽结构> 85%。
摘要:
A polycarbonate resin that after alkaline hydrolysis with sodium hydroxide contain an amount of 0.01 to 150 ppm of carbamate compounds according to formula (1) wherein R1 and R2 independently of one another denote hydrogen or C1-C12-alkyl, or together denote C4-C12-alkylidene, and R3 and R4 independently of one another denote hydrogen, C1-C12-alkyl or phenyl, or together with the carbon atom to which they are bonded form cyclohexyl or trimethylcyclohexyl, said amount measured after alkaline hydrolysis with sodium hydroxide by high pressure liquid chromatography.
摘要:
This invention relates to an optical recording medium in which at least a recording layer and a light transmitting layer are sequentially formed on a substrate and in which the light is illuminated from the light transmitting layer side for recording and/or reproducing information signals, said substrate comprising an injection molded part, and said substrate having a Young's modulus E of at least 2.15 GPa and a Q factor of lower than 160 measured at 25° C. at 2000 Hz in accordance to ASTM E 756-05 05 and a transcriptability of the pit/groove structure of >85%.
摘要翻译:本发明涉及一种光记录介质,其中至少记录层和透光层依次形成在基板上,并且其中光从光透射层侧照射以用于记录和/或再现信息信号,所述基板 包括注塑部件,并且所述基材根据ASTM E 756-05 05在2000Hz下在25℃下测量的杨氏模量E为至少2.15GPa和低于160的Q因子,并且其转录率 坑/槽结构> 85%。