Abstract: Novel compounds which increase a response speed of a liquid crystal composition by mixing with a liquid composition are represented by the general formula (I): ##STR1## wherein R represents an alkyl group having from 1 to 10 carbon atoms, X represents a hydrogen atom, a methyl group, an ethyl group or a halogen atom, and Y represents an unsubstituted aromatic heterocyclic ring.

Abstract: A record display medium is provided which can offer a high display contrast and is less likely to cause a lowering of contrast or disappearance of display even in low temperature and high temperature regions. A polymeric material for a liquid crystal/polymer composite film comprising a liquid crystal present in a polymer matrix, a liquid crystal/polymer composite film using the material, and use of the record display medium are also provided. The polymeric material for a liquid crystal/polymer composite film comprising a liquid crystal present in a polymer matrix has a glass transition temperature of 150.degree. C. or above and is insoluble in water.

Abstract: Compounds of the general formula ##STR1## have a pronounced tendency to form liquid crystalline S (smectic) phases. Thus, optically inactive compounds of the formula I also have a tilted smectic phase, in particular an S.sub.C phase, in addition to a nematic phase. In contrast, many optically active compounds of the formula I additionally have, inter alia, a tilted smectic chiral phase, in particular a chiral S.sub.C phase, in addition to a cholesteric phase. The stated compounds are therefore particularly suitable as components and as dopants, respectively, for the preparation of a very wide range of liquid crystalline mixtures. The class of compounds comprising compounds of the general formula I offers a broad range of novel components and mixtures for optimization and modification of liquid crystalline mixtures.

Abstract: A foamable drilling fluid for use in well operations such as deep water offshore drilling where risers are not employed in returning the fluid to the surface mud pit. A preferred foamable drilling fluid comprises a prehydrated clay such as bentonite, sea water, a surfactant selected from the group consisting of .alpha.-olefinsulfonates, alkylpolyglycosides, alcohol sulfates, salts of ethoxylated alcohol sulfates, and a stabilizing surfactant consisting of cocoamine betaine. The stabilized foam drilling fluid resists foam breakdown upon drilling cessation, prevents fluid loss to reduce filter cake buildup and increases the carrying capacity of cuttings and other solids. In addition, a foamable drilling fluid is provided including an hydraulic material selected from the group consisting of Portland cement, siliceous material like fumed silica, blast furnace slag and pozzolans such as fly ash.

Abstract: The present invention is concerned with photo cross-linkable liquid crystalline compounds of the general formula ##STR1## wherein A.sup.1 and A.sup.2 each represent a cross-linkable, mesogenic residue,liquid crystalline mixtures which contain such compounds and their use in the cross-linked state as optical components.

Abstract: A process for the treatment of oil wells having a high content of "acid gases", comprises circulating through or pumping into the well a slurry comprising a water-soluble, solid salt and a saline solution, which slurry does not react with the "acid gases" and which has a density of more than 13 and preferably of at least 14 lb/gal.

Abstract: A liquid crystal optical device including: a liquid crystal/polymer composite film including matrix polymer composed mainly of a transparent resin having an ionic dissociative group and, dispersed therein, a liquid crystal particle; and conductive substrates sandwiching the liquid crystal/polymer composite film therebetween, at least one of the conductive substrates being transparent.

Abstract: A chiral nematic liquid crystal composition which has a broad d/P margin, particularly for corresponding to a large size of LCD panel, while satisfying various characteristics sought for STN display mode, and which contains as a first component, at least one member of compounds expressed by the formulas (I-a) to (I-d); as a second component, at least one member of compounds expressed by the formulas (II) to (V); and as a third component, cholesteryl nonanoate, ##STR1## wherein the substituents are described herein.

Abstract: A method of increasing the penetration rate of a drill string within a deviated well bore is disclosed. The method includes providing a drill string with a drilling bottom hole assembly, and rotating the bit in order to create the deviated well bore as well as a filter cake on the walls of the well bore. A pill comprising a spherical bead is prepared and pumped down into the well bore. The pill is allowed to migrated to the low side of the bore hole so that tortuosity is reduced. A method of slide drilling, batch drilling, and running a liner in a well is also disclosed utilizing the spherical beads. In the novel methods disclosed, the spherical beads are allowed to migrate to the low side of the bore hole and are allowed to penetrate through the bore hole's filter cake.

Abstract: A liquid crystal compound represented by formula (I): ##STR1## wherein R.sub.1 represents an alkyl group having from 3 to 18 carbon atoms; R.sub.2 represents an alkyl group having from 3 to 18 carbon atoms; X represents ##STR2## Y represents ##STR3## (A) and (B) each represents a group selected from the group consisting of ##STR4## and ##STR5## and * indicates an optically active center.

Abstract: The invention relates to cholesteric liquid-crystalline polymers containing at least one colored comonomer which absorbs light in the visible wavelength region. The colored comonomers can be bifunctional hydroxyl, amino and/or carboxyl derivatives of anthranthrone, anthraquinone, dioxazine, phthalocyanine, quinacridone, diketopyrrolopyrrole, perylene, perinone, azomethine or azo pigments or aminostilbenecarboxylic acids. Coatings containing such polymers are distinguished by coloristic effects which depend on the viewing angle and cannot be achieved by absorption pigments alone or by CLCP effect coatings.

Abstract: Liquid-crystalline compounds of the formula I ##STR1## R is H, an alkyl or alkylene radical, Z.sup.1 and Z are each, independently of one another, --CH.sub.2 CH.sub.2 --, --CH.dbd.CH--,--C.tbd.C-- or a single bond, and one of the radicals Z.sup.1 and Z is alternatively --(CH.sub.2).sub.4 -- or --CH.dbd.CH--CH.sub.2 CH.sub.2 --,A is trans-1,4-cyclohexylene in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by --O--,A.sup.1 is trans-1,4-cyclohexylene in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by --O--, or is 1,4-phenylene which is unsubstituted or monosubstituted or disubstituted by fluorine and/or Cl atoms and in which, in addition, one or two CH groups may be replaced by N,W is --O--,Q is a single bond,m, o, s, r and t are as defined below,Y is F, Cl, OCF.sub.3, CHF.sub.2, OCHF.sub.2 or OCHF, and can be CF.sub.3,are suitable as components for liquid-crystalline media.

Abstract: The thermostability of an aromatic polyphosphate composition an be improved by the addition of an effective amount of a hydroxy-terminated aromatic polyphosphate composition for such.

Abstract: Mixtures of liquid-crystalline compounds comprising at least two different substances of the formula I ##STR1## where Z.sup.1 and Z.sup.2, independently of one another, are polymerizable groups,Y.sup.1 and Y.sup.2, independently of one another, are each a direct bond, --O--, --COO--, --OCO-- or --S--,A.sup.1 and A.sup.2, independently of one another, are spacers, andR.sup.1, R.sup.2 and R.sup.3 are conventional substituents,and novel compounds of the above formula where at least two of Z.sup.1, Z.sup.2, Y.sup.1, Y.sup.2, A.sup.1 and A.sup.2 are not identical, are described. The novel mixtures and compounds are suitable, inter alia, as base material for color-effect materials and piezomaterials, preferably in chirally doped form.

Abstract: A liquid crystal light composite in which discrete volumes of a liquid crystal material are dispersed in a matrix material is produced by a process in which a reactive additive formulation is added and photopolymerized. The reactive additive formulation includes mono- and multifunctional compounds in specified proportions and a photoinitiator. The reactive additive formulation reduces the operating field and may also improve other electro-optical properties.

Abstract: An optically active compound of the formula (I) according to claim 1 is suitable as a component for a liquid crystal composition providing improved response speed. The optically active compound of the formula (I) is characterized by having a fluorine-substituted optically active cite and ##STR1## group connected by 1-6 methylene groups. The above liquid crystal composition is useful as an element of a liquid crystal device and a display apparatus providing a good display characteristics.

Abstract: The invention relates to mixtures comprising acetals and oleophilic alcohols and/or oleophilic esters which are suitable for the preparation of inverted emulsion drilling muds and emulsion drilling muds. They completely or partly replace here the base oils, diesel oil, purified diesel oil, white oil, olefins and alkylbenzenes known to date.The invention furthermore relates to the use of the inverted emulsion drilling mud and emulsion drilling mud as claimed in claim 10.

Abstract: A ferroelectric liquid crystal device is described. The device comprises a pair of substrates, an electrode arrangement formed on the inside surface of the substrates, an orientation control surface provided on the inside surface of one of said substrates, and a blended ferroelectric liquid crystal disposed between the substrates. By suitably preparing the liquid crystal, multi-micro-domains are formed in the liquid crystal. By virtue of the multi-micro-domains, the contrast ratio and the response speed are significantly improved.

Abstract: A method for forming a resonator in a semiconductor laser device comprises the steps of; filling with a resin a gap surrounding the side surfaces of the waveguide for a resonator other than the end-surface to be polished; polishing the end-surface and the resin surrounding it; forming a predetermined optical coating on the polished end-surface and the resin in the state of the laser waveguide and the electrode being embedded; and removing the embedding resin. Both the bending of polished end-surfaces and the entering of the thin film into the side surface of the laser waveguide is prevented so that a high smooth end-surface of mirror coating for resonator is achieved. Furthermore, any crystals are used for a substrate carrying a semiconductor laser structure with a resonator even if that crystal is of non-cleavage, according to that method.

Abstract: Novel brominated tetrabromophthalate diesters, such as bis(2,3-dibromopropyl) tetrabromophthalate, and flame retardant organic polymer compositions containing such brominated diesters are provided.