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61. 发明授权

US4632798A Encapsulation of electronic components with anisotropic thermoplastic polymers 失效
标题翻译：用各向异性热塑性聚合物封装电子部件
公开(公告)号：US4632798A
公开(公告)日：1986-12-30
申请号：US619608
申请日：1984-06-18
申请人： Nancy C. Eickman , Charles E. McChesney , Gary E. Williams , Hyun-Nam Yoon
发明人： Nancy C. Eickman , Charles E. McChesney , Gary E. Williams , Hyun-Nam Yoon
IPC分类号： C08G63/60 , C08K3/36 , C08L77/12 , H01B3/42 , H01L23/29 , B29C45/14
CPC分类号： H01L23/293 , C08G63/605 , C08K3/36 , C08L77/12 , H01B3/42 , H01L2924/0002 , Y10T428/239
摘要： An improved thermoplastic molding composition is provided which is particularly suited for use in the impervious void-free encapsulation on a relatively expeditious basis of an electronic component wherein the preformed electronic component is positioned in a mold cavity prior to the introduction of the molding composition via injection molding. The molding composition comprises a melt processable thermotropic liquid crystalline polymer which is of a relatively low weight average molecular weight of approximately 4,000 to 25,000 (e.g. approximately 4,000 to 10,000) and which is substantially incapable of further chain growth upon heating. Uniformly dispersed within the liquid crystalline polymer is approximately 40 to 80 percent by weight (e.g. approximately 50 to 75 percent by weight) of a particulate inorganic material (preferably of silicon dioxide) which serves to advantageously decrease its volumetric coefficient of thermal expansion and to advantageously increase its thermal conductivity. In a preferred embodiment the electronic component which is encapsulated is a semiconductor device, such as relatively delicate quad or dual-in-line integrated circuit device which is assembled onto a flat prestamped lead frame or other conductive device having a plurality of leads which extend outside the area which is encapsulated. The resulting encapsulated electronic component is well protected in spite of the relatively low molecular weight of the liquid crystalline polymer and is capable of satisfactory service for an extended period of time even if adverse environmental conditions are encountered. A rugged commonly non-burning and relatively inexpensive package is provided.
摘要翻译：提供了一种改进的热塑性模塑组合物，其特别适合于在电子部件的相对快速的基础上用于不透水的无空隙的封装，其中在通过注射引入模塑组合物之前将预成型的电子部件定位在模腔中成型。模塑组合物包含熔体加工的热致液晶聚合物，其具有约4,000至25,000（例如约4,000至10,000）的相对低的重均分子量，并且其在加热时基本上不能进一步链生长。均匀分散在液晶聚合物内的颗粒无机材料（优选为二氧化硅）为约40至80重量％（例如约50至75重量％），其用于有利地降低其体积热膨胀系数并且有利地增加其导热性。在优选实施例中，被封装的电子部件是半导体器件，例如相对精密的四线或双列直插集成电路器件，其被组装到扁平预压引线框架或其它导电器件上，该器件具有多个引线，被封装的区域。尽管液晶聚合物的分子量相对较低，但是所得到的封装的电子部件被很好地保护，并且即使遇到不利的环境条件，也能够长时间地满足服务。提供坚固的通常不燃烧和相对便宜的包装。

62. 发明授权

US4574066A Process for the expeditious formation of a high strength shaped article of poly(6-oxy-2-naphthoate-4-oxybenzoate) 失效
标题翻译：用于快速形成聚（6-氧-2-萘甲酸-4-羟基苯甲酸酯）的高强度成型制品的方法
公开(公告)号：US4574066A
公开(公告)日：1986-03-04
申请号：US583643
申请日：1984-02-27
申请人： John D. Gibbon , Terry E. Lawler , Hyun-Nam Yoon , Larry F. Charbonneau
发明人： John D. Gibbon , Terry E. Lawler , Hyun-Nam Yoon , Larry F. Charbonneau
IPC分类号： C08J5/18 , D01F6/84 , D01D1/02 , D01D5/08 , D01D10/02
CPC分类号： C08J5/18 , D01F6/84 , C08J2367/00
摘要： Melt extruded poly(6-oxy-2-naphthoate-4-oxybenzoate) shaped articles of relatively high strength and modulus are produced in a lesser period of time than commonly heretofore required in the prior art. The required polymer is capable of exhibiting an anisotropic melt phase and is formed through the reaction of 6-acetoxy-2-naphthoic acid and 4-acetoxybenzoic acid under a combination of melt polymerization conditions which surprisingly has been found to yield a shaped article following melt extrusion which may be heat strengthened in an unusually brief period of time (i.e. two hours or less). The polymerization is catalyzed by a potassium salt (e.g. potassium acetate), and the polymerization conditions require a relatively highly elevated final polymerization temperature. Substantially all of the acetic acid by-product is removed from the polymerization zone prior to concluding the polymerization under reduced pressure conditions. The process of the present invention through the reduction of the required heat strengthening time accordingly makes possible a substantial productivity increase for a given production facility.
摘要翻译：熔融挤出的聚（6-氧基-2-萘甲酸-4-羟基苯甲酸酯）成形制品具有相对高的强度和模量，在比现有技术中通常要求的更短的时间内生产。所需的聚合物能够显示出各向异性的熔融相，并且通过在熔融聚合条件的组合下通过6-乙酰氧基-2-萘甲酸和4-乙酰氧基苯甲酸的反应而形成，其令人惊奇地发现在熔融后产生成型制品挤出可能在非常短暂的时间段内（即两小时或更短）热加强。聚合由钾盐（例如乙酸钾）催化，并且聚合条件需要相当高的最终聚合温度。在减压条件下聚合结束之前，基本上将所有的乙酸副产物从聚合区中除去。因此，通过减少所需的热强化时间，本发明的方法使得对于给定的生产设备可以显着提高生产率。

63. 发明授权

US4562244A Process for forming thermally stable thermotropic liquid crystalline polyesters of predetermined chain length utilizing aliphatic dicarboxylic acid 失效
标题翻译：使用脂族二羧酸形成具有预定链长的热稳定的热致液晶聚酯的方法
公开(公告)号：US4562244A
公开(公告)日：1985-12-31
申请号：US595004
申请日：1984-03-29
申请人： Hyun-Nam Yoon
发明人： Hyun-Nam Yoon
IPC分类号： C08G63/60 , C08G69/44 , C08G63/06 , C08G63/16
CPC分类号： C08G63/605 , C08G69/44
摘要： An improved polymerization process is provided for the formation of a polyester which is capable of forming an anisotropic melt phase and which optionally may include amide linkages. An approximately 0.25 to 4 percent molar excess of aliphatic dicarboxylic acid monomer containing 4 to 12 carbon atoms (e.g. azelaic acid) and/or an esterified derivative thereof is provided in the polymerization zone during the polymerization reaction. Such monomer imparts dicarboxyaliphatic units to the interior of the resulting polymer chains and causes the polymer chains to terminate in carboxylic acid end groups and/or an esterified derivative thereof wherein the polymer chains achieve a predetermined average chain length through the depletion of other monomers present in the polymerization zone. The resulting polyester unlike the usual product of the prior art is substantially incapable of additional chain growth upon subsequent heating and accordingly may be relied upon to maintain a substantially constant viscosity during melt processing regardless of the duration of heating.
摘要翻译：提供改进的聚合方法用于形成能够形成各向异性熔融相的聚酯，并且任选地可以包括酰胺键。在聚合反应期间，在聚合区域中提供了约0.25至4摩尔过量的含有4至12个碳原子的脂族二羧酸单体（例如壬二酸）和/或其酯化衍生物。这样的单体将二羧脂肪族单元赋予所得聚合物链的内部，并使聚合物链终止于羧酸端基和/或其酯化衍生物中，其中聚合物链通过其中存在的其它单体的消耗而达到预定的平均链长聚合区。所得聚酯与现有技术的通常产品不同，在随后的加热中基本上不能增加链条生长，因此可以依赖于在熔融加工期间保持基本恒定的粘度，而不管加热的持续时间如何。

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