摘要:
A process for producing (i) a 1,3-bis(dicarboxyphenyl)disiloxane derivative represented by the general formula ##STR1## wherein Rs and R's independently of one another denote methyl or phenyl or (ii) a 1,3-bis(dicarboxyphenyl)-disiloxane derivative dianhydride represented by the general formula ##STR2## wherein Rs and R's are as defined above, the process comprising coupling a Grignard reagent of halo-o-xylene with a disubstituted halosilane represented by the general formula ##STR3## wherein R and R' are as defined above and X denotes halogen, to form a dimethylphenyl(disubstituted silane) represented by the general formula ##STR4## wherein R and R' are as defined above, hydroxylating the dimethylphenyl(disubstituted silane) to form a dimethylphenyl(disubstituted hydroxysilane) represented by the general formula ##STR5## wherein R and R' are as defined above, to form a 1,3-bis(dimethylphenyl)-disilanedehydrating-condensing the dimethylphenyl-(disubstituted hydroxysilane derivative represented by the general formula ##STR6## wherein Rs and R's are as defined above, and oxidizing the 1,3-bis(dimethylphenyl)disilane derivative to yield the intended 1,3-bis(dicarboxyphenyl)disiloxane derivative of general formula [V], orfurther comprising the dehydration ring closure of this product to form a 1,3-bis(dicarboxyphenyl)-disiloxane derivative dianhydride of general formula [VI], mixing the resulting isomeric mixture with an ether solvent, and recovering the formed precipitate to yield a white powder of the intended product of general formula [VI].
摘要:
A phenolic polymer obtained by reacting a phenolic compound with a bis(hydroxyalkyl)benzene, followed by alkylation of ortho positions or para position with respect to the hydroxyl group of the terminal phenol groups of the produced polymer is suitable for use as a heat resistant antioxidant for thermoplastic resins
摘要:
A polyimide obtained from a polyamide-acid or polyamide-acid ester prepared by reacting dicyclohexyl-3,4,3', 4'-tetracarboxylic acid or dinanhydride with a diamine is excellent in transparency, heat resistance and mechanical properties, said polyimide being able to be obtained at a lower temperature, and particularly suitable for an orientation film used in a liquid crystal display device.
摘要:
A phenolic polymer obtained by reacting a phenolic compound with a bis(hydroxyalkyl)benzene, followed by alkylation of ortho positions or para position with respect to the hydroxyl group of the terminal phenol groups of the produced polymer is suitable for use as a heat resistant antioxidant for thermoplastic resins.
摘要:
A synthetic resin composition comprising a synthetic resin and a special phenolic polymer is stabilized for a long period of time and excellent in heat resistance and light resistance.
摘要:
Disclosed are a para- or meta-terphenyl-3,4,3",4"-tetracarboxylic acid or a dianhydride and a process for preparing the same. The para- or meta-terphenyl-3,4,3",4"-tetracarboxylic acid or a dianhydride thereof according to the present invention is a novel compound which is useful as a raw material for a polyimide having higher heat resistance and so on.
摘要:
An arrangement of a mass intake air flow measurement device suitable for integrating a humidity sensing device as well as a temperature sensing device and a pressure sensing device is provided. A second bypass passage 501 bypassing a bypass passage 205 is formed and a humidity sensing device 500 is mounted in the second bypass passage 501. A second bypass passage inlet 502 and a second bypass passage outlet 503 formed in a wall surface of the bypass passage 205 are opened parallel to the direction of flow of air flowing in the bypass passage 205.
摘要:
In relation to a humidity sensor sensitive to water and contamination, a sensor implementation structure that achieves both protection performance against water and contaminants and measurement performance such as humidity responsiveness is provided. A sensor structure has a mass airflow measurement element that measures a mass airflow flowing in an intake pipe, a humidity sensing element that senses humidity of air flowing in the intake pipe, a housing structural component having a connector that carries out input/output to/from outside and a terminal component of the connector, and a bypass passage that is composed by using part of the housing structural component and takes in part of the air that flows in the intake pipe, the mass airflow measurement element being mounted in the bypass passage; wherein space is provided in the housing structural component in the vicinity of the bypass passage, the humidity sensing element is mounted in the space.
摘要:
A light-emitting apparatus is provided with: a light-emitting module; a control circuit unit configured to control the lighting of the light-emitting module; a heat-radiating substrate configured to support the light-emitting module and the control circuit unit in such a manner as to recover the heat produced by the light-emitting module and the control circuit unit; and a connection support unit mounted on the heat-radiating substrate in such a state as to support an electrically conductive member by which to electrically connect the light-emitting module and the control circuit unit.