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公开(公告)号：US06344592B1
公开(公告)日：2002-02-05
申请号：US09467212
申请日：1999-12-20
IPC分类号： C07C3118
摘要： A method of producing a highly pure trimethylolpropane from a crude trimethylolpropane obtained by a reaction of n-butyl aldehyde and formaldehyde in the presence of a basic catalyst in a two-stage process of an aldol condensation and a crossed Cannizzaro reaction. Since a high-boiling component and an inorganic salt are removed in advance from the crude trimethylolpropane, hardly removable impurities such as condensation products in the crude trimethylolpropane are changed in the subsequent heat treatment under acidic conditions to components easily removable by distillation. By distilling the heat-treated crude trimethylolpropane, a highly pure trimethylolpropane with a low content of remaining formaldehyde and a low coloring degree is easily obtained.
摘要翻译： 在碱式催化剂存在下，在醛醇缩合和交叉的坎尼扎罗反应的两阶段过程中，通过正丁醛和甲醛的反应获得的粗三羟甲基丙烷制备高纯度三羟甲基丙烷的方法。 由于预先从粗三羟甲基丙烷中除去高沸点组分和无机盐，所以在酸性条件下的后续热处理中，在粗三羟甲基丙烷中几乎不可除去的杂质如缩合产物发生变化，可以通过蒸馏容易地除去。 通过蒸馏热处理的粗三羟甲基丙烷，容易获得具有低残留甲醛含量和低着色度的高纯度三羟甲基丙烷。
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公开(公告)号：US6080896A
公开(公告)日：2000-06-27
申请号：US302058
申请日：1999-04-29
摘要： A process for producing a polyhydric alcohol with high selectivity by subjecting formaldehyde and a specific aliphatic aldehyde to an aldol condensation reaction in the presence of a base catalyst, and then subjecting the resultant reaction product to a crossed Cannizzaro reaction, while reacting a solution containing a 2-substituted-2-alkanal, formed as a byproduct during the aldol condensation reaction, with water or formaldehyde in the presence of the base catalyst, and thereafter reacting the resultant mixture with the aliphatic aldehyde.
摘要翻译： 一种通过在碱性催化剂的存在下使甲醛和特定的脂族醛进行醛醇缩合反应，以高选择性制造多元醇的方法，然后使所得反应产物进行交叉的坎尼扎罗反应，同时使含有 在醛醇缩合反应中作为副产物形成的2-取代-2-链烷醛与水或甲醛在碱催化剂存在下反应，然后使所得混合物与脂族醛反应。
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公开(公告)号：US5608121A
公开(公告)日：1997-03-04
申请号：US533513
申请日：1995-09-25
CPC分类号： C07C29/38
摘要： There is disclosed a process for producing a polyhydric alcohol which comprises reacting an aliphatic aldehyde with formaldehyde in the presence of a base compound consisting essentially of a hydrogencarbonate and a carbonate which have been formed by the oxidation or hydrolysis of a formic acid salt, in particular, the process according to the above process wherein a formic acid salt which has been by-produced by the reaction of an aliphatic aldehyde with formaldehyde is oxidized or hydrolyzed in the presence of a noble metal catalyst or a nickel catalyst in a reductive state to form a base compound consisting essentially of a hydrogencarbonate and a carbonate and this base compound is circulated through the reaction of the aldehyde and formaldehyde and is reused as the base compound. The above process enables easy and highly efficient production of high quality polyhydric alcohols substantially without by-producing a formic acid salt with a low value-added.
摘要翻译： 公开了一种生产多元醇的方法，该方法包括使脂族醛与甲醛在碱性化合物的存在下反应，所述碱性化合物主要由碳酸氢盐和碳酸酯组成，其通过甲酸盐的氧化或水解形成，特别是 ，根据上述方法的方法，其中通过脂族醛与甲醛的反应副产生的甲酸盐在还原状态的贵金属催化剂或镍催化剂存在下被氧化或水解形成 基本上由碳酸氢盐和碳酸盐组成的碱性化合物，该碱性化合物通过醛和甲醛的反应循环，并重复使用作为碱性化合物。 上述方法能够容易且高效地生产高品质的多元醇，基本上不产生具有低附加值的甲酸盐。
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公开(公告)号：US6077980A
公开(公告)日：2000-06-20
申请号：US118419
申请日：1998-07-17
摘要： A process for producing a polyhydric alcohol which comprises subjecting formaldehyde and a specific aliphatic aldehyde to an aldol condensation reaction in the presence of a base catalyst, and then subjecting the resultant reaction product to a crossed Cannizzaro reaction, while separating 2-alkenal formed as a byproduct during the aldol condensation reaction, prior to the completion of the crossed Cannizzaro reaction. Also a process for producing a polyhydric alcohol which comprises reacting formaldehyde with a 2-alkenal, such as that obtained in the aldol condensation reaction, in the presence of a base catalyst, then subjecting the resultant reaction product and a specific aliphatic aldehyde to an aldol condensation reaction, and subsequently subjecting the resultant reaction product to a crossed Cannizzaro reaction. The processes provide a polyhydric alcohol in high selectivity with a minimum excess of formaldehyde, without substantially by-producing a 2-alkenal.
摘要翻译： 一种制备多元醇的方法，其包括在碱催化剂存在下使甲醛和特定的脂族醛进行醛醇缩合反应，然后将所得反应产物进行交叉的坎尼扎罗反应，同时分离形成的二烯烃 在醛醇缩合反应期间，在交叉的Cannizzaro反应完成之前副产物。 还有一种生产多元醇的方法，它包括在碱催化剂的存在下使甲醛与醛缩醇反应得到的2-烯醛反应，然后将得到的反应产物和特定的脂族醛进行醛醇 缩合反应，随后使得到的反应产物进行交叉的坎尼扎罗反应。 该方法以高选择性提供最少过量的甲醛的多元醇，而基本上不产生2-烯醛。
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公开(公告)号：US5840994A
公开(公告)日：1998-11-24
申请号：US820080
申请日：1997-03-19
CPC分类号： C07C41/01
摘要： A process for producing ditrimethylolpropane which comprises reacting trimethylolpropane, 2-ethylacrolein, and formaldehyde in the presence of a basic catalyst. Ditrimethylolpropane is produced efficiently and industrially advantageously.
摘要翻译： 一种制备二羟甲基丙烷的方法，其包括在碱性催化剂存在下使三羟甲基丙烷，2-乙基丙烯醛和甲醛反应。 双三羟甲基丙烷在工业上有利地产生。
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公开(公告)号：US07087800B2
公开(公告)日：2006-08-08
申请号：US09874276
申请日：2001-06-06
IPC分类号： C07C27/26
CPC分类号： C07C29/38 , C07C29/80 , C07C29/86 , Y02P20/582 , C07C31/22
摘要： A process for producing a polyol by reacting an aliphatic aldehyde with formaldehyde in the presence of a basic catalyst, which comprises a step of concentration which comprises removing water and unreacted formaldehyde from a reaction liquid by distillation; a step of extraction which comprises extracting the polyol from a concentrated reaction liquid with an extracting reagent; a step of washing with water which comprises washing an extract liquid with water and separating the liquid into an oil layer containing the polyol and an aqueous layer; wherein by useing an specific aliphatic aldehyde as the extracting agent and recovering the extracting reagent from the oil layer containing the polyol after adjusting pH of the oil layer, a high purity polyhydric alcohol can be obtained at a high yield with suppressed formation of byproducts such as acetal compounds and aldol compounds.
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公开(公告)号：US07153999B2
公开(公告)日：2006-12-26
申请号：US10051025
申请日：2002-01-22
IPC分类号： C07C59/10
CPC分类号： C07D319/12 , C07C51/377 , Y02P20/55 , C07C59/10
摘要： In the method of the present invention, a dimethylolcarboxylic acid is produced by reacting a trimethylolalkane and formaldehyde to prepare a cyclic formal having a formal protecting group, followed by the oxidation of the cyclic formal by using nitric acid as an oxidizing agent to prepare a cyclic carboxylic acid which is then subjected to cleavage to remove the formal protecting group. The formal protecting group protects two of the methylol groups against the oxidation to enable the production of the dimethylolcarboxylic acid with a high selectivity.
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公开(公告)号：US08583404B2
公开(公告)日：2013-11-12
申请号：US13023219
申请日：2011-02-08
IPC分类号： G04F1/00
CPC分类号： G04F1/00 , G01S17/026 , G01V8/10 , G01V8/16
摘要： A photoelectric sensor comprises a control unit which performs a measuring process for data on an amount of light input from a light-receiving unit. The control unit measures the length TPS of period (from point a to point d) from when measurement data starts to change in the direction of a threshold P0 to when the amount of received light returns to the level at which the measurement data started to change, and the length TON of period (from point b to point c) for which the detection signal is ON-level. The control unit then outputs information on a margin for TPS with respect to TON on a display unit provided for the photoelectric sensor or to an external device in order to display them.
摘要翻译： 光电传感器包括对从光接收单元输入的光量的数据执行测量处理的控制单元。 控制单元测量从测量数据开始到阈值P0的方向上变化到周期（从点a到点d）的长度TPS，当接收光的量返回到测量数据开始改变的水平时 ，以及检测信号为ON电平的周期（从点b到点c）的长度TON。 然后，控制单元在为光电传感器设置的显示单元或外部设备上输出关于TON的TPS裕度的信息，以便显示它们。
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公开(公告)号：US07509031B2
公开(公告)日：2009-03-24
申请号：US11105399
申请日：2005-04-14
申请人： Atsushi Iwamoto
发明人： Atsushi Iwamoto
IPC分类号： H04N5/00
CPC分类号： H04N5/76 , H04N5/85 , H04N9/8042
摘要： In an optical disk recorder, an optimum threshold value (M′) of a front-end buffer is calculated from data size, signal transfer rate (Rt) and signal write rate (Rw). Writing the signal to the optical disk is performed multiple times each immediately after the storage amount reaches the optimum threshold value (M′), while continuing buffer storage to the front-end buffer. By performing the writing, time (T3) at which the signal transfer from a back-end buffer to the front-end buffer is ended can be made substantially simultaneous with time (T4) at which the signal writing by an optical pickup is ended, whereby time required for signal writing can be reduced.
摘要翻译： 在光盘记录器中，根据数据大小，信号传送速率（Rt）和信号写入速率（Rw）计算前端缓冲器的最佳阈值（M'）。 在存储量达到最佳阈值（M'）之后，立即执行多次将信号写入光盘，同时持续缓冲存储到前端缓冲器。 通过执行写入，可以使从后端缓冲器到前端缓冲器的信号传送结束的时间（T3）基本上与光学拾取器的信号写入结束的时间（T4）同时进行， 从而可以减少信号写入所需的时间。
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公开(公告)号：US20070206459A1
公开(公告)日：2007-09-06
申请号：US11712485
申请日：2007-03-01
IPC分类号： G11B7/00
CPC分类号： G11B7/0945 , G11B7/08511 , G11B7/1369 , G11B7/13925 , G11B7/13927 , G11B2007/0013
摘要： An optical disc apparatus includes a spherical aberration correction element for correcting spherical aberration and a preadjustment unit for obtaining setting of a spherical aberration correction element for correcting spherical aberration appropriately in a case where a focus position of a light beam emitted from a light source is adjusted on each of recording layers of an optical recording medium every time when the optical recording medium is loaded to the apparatus.
摘要翻译： 光盘装置包括用于校正球面像差的球面像差校正元件和用于在调整从光源发射的光束的聚焦位置被调整的情况下适当地获得用于校正球面像差的球面像差校正元件的设置的预调整单元 每当光学记录介质被加载到设备时，在光学记录介质的每个记录层上。
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