摘要:
The present invention includes a step of separating an effluent produced in a hydrogenation step of making tetrachlorosilane (STC) react with hydrogen into trichlorosilane (TCS), into a chlorosilane fraction containing a hydrocarbon and a TCS fraction, and a chlorination step of making the chlorosilane fraction containing the hydrocarbon react with chlorine to form STC and a substance containing a chlorinated hydrocarbon, wherein the effluent containing STC produced in the chlorination step is circulated to the hydrogenation step. In the chlorination step, the chlorosilane fraction containing a hydrocarbon (capable of containing hyper-hydrogenated chlorosilanes) having a boiling point close to TCS is hyper-chlorinated to be converted and acquire a higher boiling point, which facilitates the hyper-chlorinated chlorosilanes and the hyper-chlorinated hydrocarbons to be separated into high concentration, and increases the purity of TCS to be finally obtained.
摘要:
The present invention provides a method for obtaining high purity chlorosilanes from chlorosilanes containing boron impurities and phosphorus impurities. On the basis of the finding that solid by-product formation in the purification of chlorosilanes by adding an aromatic aldehyde results from a catalytic reaction by iron ions or rust-like iron, a Lewis base having a masking effect is added to chlorosilanes. Examples of the Lewis base include a divalent sulfur-containing compound and an alkoxysilane. The divalent sulfur-containing compound is preferably a compound represented by the formula: R—S—R′ (wherein R is a hydrocarbon group or a carbonyl group; and the sum of the carbon atoms in R and R′ is 7 or more), and the alkoxysilane is preferably a compound represented by the formula: RxSi(OR′)4-x (wherein R and R′ are each an alkyl group having 1 to 20 carbon atoms).
摘要:
A barcode scanner comprising a laser driving circuit to drive a laser by a pulse signal generated by an oscillator, a preamplifier to amplify a voltage of a barcode signal from a photodetector corresponding to a reflected light from a barcode scanned by a light output of the laser driven by the pulse signal, a high-pass filter to remove a direct current component contained in an output signal of the preamplifier, a variable gain amplifier which controls an amplification gain of an output signal of the high-pass filter and performs automatic gain control to set an output level almost constant, a synchronous detector to detect a pulse signal contained in an output signal of the variable gain amplifier in synchronization with the output pulse of the oscillator, and a binarization circuit to binarize an output signal of the synchronous detector.
摘要:
This invention provides twisted nematic liquid crystal compositions obtained by adding a cyclohexane ring-containing optically active compound of the following general formula (1) to a mixture of nematic liquid crystal compounds including at least one silacyclohexane compound, as well as guest-host liquid crystal compositions and liquid crystal display devices utilizing the same. ##STR1##
摘要:
Silacyclohexane compounds of the following formula (I) or (II) along with intermediate compounds therefor are described ##STR1## wherein R is an organic residue, one of ##STR2## represents a trans-1-sila-1,4-cyclohexylene group or trans-4-sila-1,4-cyclohexylene group having a substituent of H, F, Cl or CH.sub.3, and the other represents a trans-1,4-cyclohexylene group, or such a trans-1-sila-1,4-cyclohexylene group or trans-4-sila-1,4-cyclohexylene group as defined above, n is 0 or 1, L.sub.1 represents H or F, L.sub.2 represents H, F or Cl, and Z represents CN, F, Cl or an organic residue, and ##STR3## The processes for preparing the compounds (I) and (II) are also described along with liquid crystal compositions comprising the compounds and the liquid crystal devices comprising the compositions.
摘要:
A silacyclohexane compound represented by the following general formula (I). ##STR1## In this formula, R denotes a linear-chain alkyl group with a carbon number of 1-10, a mono- or di- fluoro-alkyl group with a carbon number of 1-10, a branched-chain alkyl group with a carbon number of 3-8, an alkoxyalkyl group with a carbon number of 2-7, or an alkenyl group with a carbon number of 2-8. ##STR2## denotes trans-1-sila-1,4-cyclohexylene or trans-4-sila-1,4-cyclohexylene group whose silicon at position 1 or position 4 has a substitutional group(s) of H, F, Cl or CH.sub.3. X denotes a CN, F, Cl, CF.sub.3, CF.sub.2 Cl, CHFCl, OCF.sub.3, OCHF.sub.2, OCF.sub.2 Cl, OCHFCl, R or OR group (R is the same as defined in the general formula (I)). Y.sub.2 and Z denote H or F, independently to each other. Y.sub.1 denotes H, F or Cl.
摘要:
A liquid crystal composition comprising a silacyclohexane compound represented by the following formula (I): ##STR1## wherein R and R' denote an alkyl group, a mono- or di-fluoroalkyl group, an alkoxyalkyl group or an alkenyl group; at least one of ##STR2## denotes a silacyclohexylene group whose silicon at positions 1 or 4 has a substitutional group of H, F, Cl of CH.sub.3, and the other denotes a silacyclohexylene group whose silicon at positions 1 or 4 has a substitutional group of H, F, Cl or CH.sub.3 or a cyclohexylene group; and 0-2 of the substitutional groups X on the aromatic rings denote F and the remaining X's denote H.
摘要:
A silacyclohexane compound represented by the following general formula (I). ##STR1## In this formula, R denotes hydrogen, a linear-chain alkyl group with a carbon number of 1-10, a branched-chain alkyl group with a carbon number of 3-8, an alkoxyalkyl group with a carbon number of 2-7, a fluoroalkyl group with a carbon number of 1-10 in which one or two hydrogen atoms are substituted by florine atom(s), or an alkenyl group with a carbon number of 2-8. For the groups ##STR2## at least one of these is a trans-1-sila-1,4-cyclohexylene or trans-4-sila-1,4-cyclohexylene group whose silicon at position 1 or position 4 has a substitutional group(s) of H, F, Cl or CH.sub.3, and the other denotes a trans-1,4-cyclohexylene group. X denotes a CN, F, Cl, CF.sub.3, CF.sub.2 Cl, CHFCl, OCF.sub.3, OCHF.sub.2, OCF.sub.2 Cl, OCHFCl, R or OR group (R is the same as defined earlier). Y denotes H or F. Z denotes H or F.
摘要:
The film-forming agent of the invention is a blend of a silica organosol, of which the silica particles have a specified specific surface area and specified densities of surface groups including silanol groups, alkoxy groups and trimethyl silyl groups, and a diorganopolysiloxane of a specified viscosity terminated at each molecular chain end with a silanolic hydroxy group. The film-forming agent is useful as a skin-care preparation for preventing chapping of hands of people having frequent occasions of contacting with water to exhibit durable water repellency.
摘要:
A method for the preparation of a stable silica organosol in a hydrophobic organic solvent is proposed. The method comprises (a) hydrolyzing a tetraalkoxy silane, e.g. tetraethoxy silane, in an alcoholic medium in the presence of a limited amount of water and ammonia as a catalyst under controlled conditions so as to produce a silica alcosol in which the silica particles satisfy the requirements that the alkoxy groups and silanolic hydroxy groups are bonded to the silicon atoms on the surface in densities of at least 3.5 .mu. moles/m.sup.2 and not exceeding 2 .mu. mmoles/m.sup.2, respectively, and the specific surface area S given in m.sup.2 /g and the average particle diameter D given in nm of the silica particles satisfy the relationship of S.times.D.gtoreq.5000, D being 1 nm or larger, and (b) admixing the alcosol of silica particles with an organosilicon compound selected from the group consisting of the compounds represented by the general formula R.sub.4-n SiX.sub.n, (R.sub.3 Si).sub.2 NH, or YO--(--SiR.sub.2 --O--).sub.m --Y, in which each R is, independently from the others, a hydrogen atom or a monovalent hydrocarbon group, X is a hydroxy group or an alkoxy group, Y is a hydrogen atom or an alkyl group, n is 1, 2 or 3 and m is a positive integer not exceeding 20, in an amount, for example, in the range from 0.01 to 10 moles per mole of the silica particles under agitation of the mixture to effect a reaction for the modification of the surface of the silica particles followed by replacement of the alcoholic medium with a desired organic solvent.