312 results about "Dielectric anisotropy" patented technology

The invention discloses a liquid crystal compound, the structural formula of the liquid crystal compound is as shown in the following formula I, # imgabs0. The liquid crystal compound has large dielectric anisotropy delta epsilon, high elastic constant K, good low-temperature intersolubility, small rotary viscosity gamma 1 and large elastic constant K, the liquid crystal composition containing the liquid crystal composition has large dielectric anisotropy delta epsilon, high elastic constant K, good low-temperature intersolubility, small rotary viscosity gamma 1 and large elastic constant K, and can be used for developing liquid crystal display elements or liquid crystal displays which have high response speed and can effectively improve residual images.

The present invention relates to liquid-crystalline (LC) media having positive dielectric anisotropy and to liquid-crystal displays (LCDs) containing these media, especially to displays addressed by an active matrix and in particular to LC displays of the TN, PS-TN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, XB-FFS, PS-FFS, SA-HB-FFS, SA-XB-FFS, polymer stabilised SA-HB-FFS, polymer stabilised SA-XB-FFS, positive VA or positive PS-VA type.

According to the photopolymer system based on the fluorine-containing liquid crystal, the grating device and the preparation method of the grating device, the mixed liquid crystal containing the nematic liquid crystal and the fluorine-containing liquid crystal at the same time is adopted in the photopolymer system, and therefore the polarity and dielectric anisotropy of the mixed liquid crystal material are improved; the overall electro-optical performance, uniformity and stability of the photopolymer system are improved, so that a grating device prepared based on the photopolymer system has good optical characteristics of low haze while having relatively high diffraction efficiency. Specifically, fluorine-containing biphenyl liquid crystals, fluorine-containing alkyne liquid crystals and fluorine-containing difluoromethoxy liquid crystals of which the carbon atoms of flexible side chains are 2-5, and nematic liquid crystals of which the delta epsilon is not less than 10 are selected to jointly form mixed liquid crystals; and the balance and optimization between the diffraction efficiency and haze performance of the photopolymer system and the grating device prepared from the photopolymer system are realized.

The embodiment of the invention discloses a compound, a liquid crystal composition and application thereof, relates to the technical field of liquid crystals, and is used for solving the technical problem that the service life of electronic equipment is short due to the fact that a liquid crystal material is poor in material performance and high in material performance attenuation speed. The compound has a structure as shown in a formula (I). # imgabs0 # wherein X1 and X2 are each independently selected from the group consisting of hydrogen, deuterium, tritium, at least one halogen, and at least one hydrocarbyl group, and at least one of X1 and X2 is not hydrogen. The compound has higher birefringence, better dielectric anisotropy, lower rotary viscosity, higher clearing point, better low-temperature stability and the like, and when the compound is used as a liquid crystal compound, the performance degradation speed of a liquid crystal material is slow, so that the service life of electronic equipment can be prolonged.

LCoS panels using liquid crystal (LC) media having negative dielectric anisotropy and LC media comprised therein. The liquid crystal material (LC medium) has negative dielectric anisotropy and high optical anisotropy and is particularly useful in electro-optical displays including projection systems based on vertical alignment (VA) nematic panels.

The invention relates to the technical field of heat exchange of capacitor filling polyurethane, and particularly discloses a cooling system and method and application. According to the system, through the synergistic effect of the temperature control module and the electric field control module, a temperature difference field and an electric field are constructed for the composite heat conduction module, and dielectric anisotropy nanosheets are induced to form a highly-oriented ordered structure in a resin matrix, so that the heat conduction efficiency of the capacitor is remarkably improved, the filling concentration of the dielectric anisotropy nanosheets is reduced, and the service life of the capacitor is prolonged. And directional arrangement of the dielectric anisotropic nanosheets is realized with a relatively low electric field intensity threshold. Compared with the prior art, the scheme not only breaks through the technical bottleneck of high filling amount of the traditional heat-conducting filler, but also reduces the directional driving force provided by an electric field through a field coupling effect, shows remarkable economic benefits and engineering application values, and solves the problems that the existing heat-conducting composite system is large in filling amount and poor in synergy heat-conducting property in all directions.

The present application provides a liquid crystal composition and a liquid crystal display device comprising same. The liquid crystal composition comprises at least one compound as represented by general formula I and at least one compound as represented by general formula II. On the basis of appropriate optical anisotropy, relatively high dielectric anisotropy, a relatively large elastic constant, a high response speed, a high transmittance and other properties being maintained, the liquid crystal composition provided in the present application also has a good Flicker value, relatively high low-temperature stability, a wider nematic phase temperature range and a better contrast ratio.

The invention provides a dye liquid crystal composition, a liquid crystal dimming device containing the dye liquid crystal composition and application of the dye liquid crystal composition. The dye liquid crystal composition comprises at least one liquid crystal composition A and at least one dichroic dye, and the liquid crystal composition A comprises at least one compound as shown in a general formula I. According to the dye liquid crystal composition and the preparation method thereof, by adopting the compound with a specific structure as shown in the general formula I, the dye liquid crystal composition has a relatively high clearing point, relatively low rotary viscosity, a relatively large dielectric anisotropy absolute value, proper vertical dielectric, relatively low refractive index, relatively good low-temperature storage stability and relatively good low-temperature intersolubility; the liquid crystal dimming device containing the liquid crystal compound has the advantages of better contrast ratio, better transmittance, wider temperature application range, better stability, higher response speed and lower dispersion, and can reduce the glare phenomenon in the dimming fields of buildings, traffic and the like. # imgabs0 #

Liquid-crystalline (LC) media having positive dielectric anisotropy and liquid-crystal displays (LCDs) containing these media, especially displays addressed by an active matrix and in particular energy efficient LC displays of the TN, PSTN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, XB-FFS, PS-FFS, SA-HB-FFS, SA-XB-FFS, polymer stabilised SA-HB-FFS, polymer stabilised SA-XB-FFS, positive VA or positive PS-VA type. The media have an improved long-term stability against UV radiation and elevated temperatures.

A liquid-crystal (LC) material comprising one or more compounds of the formula Ihaving negative dielectric anisotropy and the use thereof for optical, electro-optical and electronic purposes, such as for example in LC displays, in particular energy saving displays based on the ECB, IPS or FFS effect.

The invention relates to the technical field of liquid crystal display materials, in particular to a liquid crystal compound and a preparation method and application thereof, and the liquid crystal compound has a structure as shown in a general formula I: # imgabs0 # (I). The liquid crystal compound with the specific structure has the advantages of high dielectric anisotropy, good liquid crystal intersolubility and the like, the dielectric anisotropy epsilon of the liquid crystal composition can be remarkably improved when the liquid crystal compound is specifically applied to the liquid crystal composition, meanwhile, proper refractive index anisotropy n is kept, and the liquid crystal composition can be applied to the liquid crystal composition. The obtained liquid crystal composition has the remarkable characteristics of quick response and low-voltage driving.

According to the liquid crystal composition, all components (general formulas I-IV) contain F atoms, and the limitation that only part of components of a traditional liquid crystal material contain F atoms is broken through. The problems of high transparent haze and slow low-temperature response of a negative dielectric liquid crystal material are effectively solved. A traditional fluorinated compound is easy to separate from a polycyclic structure due to non-uniform F distribution, so that the optical uniformity is poor, and low-temperature viscosity drastic increase and high-temperature molecule out-of-order are difficult to improve at the same time. Through all-component F-containing design, the dielectric anisotropy is reduced, and the negative dielectric property is endowed; meanwhile, a special space structure and uniform distribution of F atoms synergistically enhance the stability of an intermolecular interaction network, maintain a low-viscosity characteristic in a wide temperature range, inhibit abnormal rise of low-temperature viscosity so as to accelerate response and reduce delay, inhibit out-of-order arrangement of high-temperature molecules, remarkably reduce the decreasing amplitude of fog-state light transmittance and improve the fog-state light transmittance. And collaborative optimization of optical uniformity, response speed and high-temperature stability is realized.

Provided is a liquid crystal composition which satisfies the following requirements: a high upper-limit temperature, a low lower-limit temperature, a low viscosity, appropriate optical anisotropy, large dielectric anisotropy, a large dielectric constant in the short-axis direction, a large ratio of the dielectric constant in the short-axis direction to the dielectric anisotropy, a large specific resistance, high stability with respect to light and heat, and a high stability with respect to light and heat. The present invention relates to a liquid crystal composition, a liquid crystal display element, and a use thereof, which have at least one of the characteristics such as high elastic constant, or a suitable balance between at least two of the characteristics. A liquid crystal composition containing, as component A, a specific compound having large optical anisotropy, it is also possible to contain a specific compound having a large dielectric anisotropy as component B, a specific compound having a small viscosity or a high upper limit temperature as component C, or a specific compound having a large dielectric constant in the minor axis direction as component D.

The present invention provides a liquid crystal composition and a liquid crystal display device thereof. The liquid crystal composition of the present invention has a high clearing point, appropriate optical anisotropy, appropriate absolute value of dielectric anisotropy, large perpendicular dielectric, large K value, small rotational viscosity, fast angular velocity, small polymer residue, good pre-tilt angle stability, small polymer layer surface roughness and large VHR value, so that the liquid crystal display device containing the liquid crystal composition has high transmittance, high contrast, high reliability and fast response speed while maintaining a wide temperature use range and appropriate threshold voltage, and can effectively accelerate the production process of PSA type liquid crystal display, improve production efficiency, and can effectively improve the problems such as "image stickiness", uneven display, "broken bright spots" existing in the existing PSA type liquid crystal display, and has high practical application value. #imgabs0#

The invention relates to a novel liquid crystal material and application thereof, a double five-membered heteroaromatic ring is used as a core structure unit of a liquid crystal molecule, so that the liquid crystal material keeps high dielectric anisotropy, and meanwhile, the rotary viscosity of the liquid crystal molecule is remarkably reduced. A polar substituent group is introduced at the tail end of a molecule, so that the electro-optical performance is further optimized, particularly, the dimming contrast ratio and the response speed are obviously improved, and the compound also has excellent damp-heat stability and can meet the requirements of application scenes such as large-area intelligent dimming windows and vehicle-mounted anti-dazzle rearview mirrors. The liquid crystal material provided by the invention not only provides excellent electro-optical performance, but also has low-voltage driving, high dimming contrast and excellent environmental stability, provides an innovative material solution for a next-generation high-speed and low-power-consumption liquid crystal display device, and has wide application prospects and good industrialization potential.

The present invention relates to the technical field of liquid crystal compounds, and in particular to a liquid crystal compound containing a polyfluorophenanthrene structure, and also to an application thereof. The liquid crystal compound provided by the present invention has a structure shown in general formula (I), and the compound has excellent properties such as high negative dielectric anisotropy, good liquid crystal mutual solubility, and relatively low rotational viscosity, and can be used to improve the performance of liquid crystal materials.

The present application provides a liquid crystal composition and a liquid crystal display device thereof. The liquid crystal composition of the present application comprises at least one compound of general formula O and at least one compound of general formula B. The liquid crystal composition of the present application has smaller polymer residue, smaller roughness, better low-temperature storage stability, smaller contact angle, better alignment effect, and better pre-tilt angle stability under the condition of maintaining proper clearing point, proper optical anisotropy, proper absolute value of dielectric anisotropy, larger K value (K 11 and K 33 ) and smaller rotational viscosity, so that the liquid crystal display device comprising the same has proper threshold voltage, better contrast, better response speed, can effectively improve the problems such as "image sticking", display unevenness, "broken bright spot" and the like existing in the existing PSA type liquid crystal display, and has higher practical application value.

A liquid-crystal (LC) material comprising a compound of formula I and a compound of formula CPY and one or more compounds of formulae IIA, IIB, IIC and IID wherein the compound of the formula CPY is excluded from the formula IIB, having negative dielectric anisotropy and the use thereof for optical, electro-optical and electronic purposes, such as for example in LC displays, in particular energy saving displays based on the ECB, IPS or FFS effect.

The present invention relates to liquid-crystalline (LC) media having positive dielectric anisotropy and to liquid-crystal displays (LCDs) containing these media, especially to displays addressed by an active matrix and in particular to LC displays of the TN, PS-TN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, XB-FFS, PS-FFS, SA-HB-FFS, SA-XB-FFS, polymer stabilised SA-HB-FFS, polymer stabilised SA-XB-FFS, positive VA or positive PS-VA type.

The present invention provides a photopolymer system based on fluorinated liquid crystal, a grating device and a preparation method thereof. In the photopolymer system provided by the present invention, a mixed liquid crystal containing both nematic liquid crystal and fluorinated liquid crystal is adopted, thereby improving the polarity and dielectric anisotropy of the mixed liquid crystal material, and improving the electro-optical performance, uniformity and stability of the overall photopolymer system, so that the grating device prepared based on this photopolymer system has good optical characteristics with low haze while having a high diffraction efficiency. Specifically, in the present invention, a fluorinated biphenyl liquid crystal, a fluorinated alkyne liquid crystal and a fluorinated difluoromethoxy liquid crystal with 2-5 carbon atoms in the flexible side chain are selected, and a nematic liquid crystal with Δε not less than 10 is selected to jointly form a mixed liquid crystal, realizing the balance and optimization between the diffraction efficiency and haze performance of the photopolymer system and the grating device prepared therefrom.

The invention provides a liquid crystal compound containing a polyfluoro substituent group, a composition and application of the liquid crystal compound. The liquid crystal compound disclosed by the invention has a structure as shown in a formula I, and has relatively high negative dielectric anisotropy, good liquid crystal intersolubility and relatively low rotary viscosity. Formula I

A liquid crystal compound represented by general formula F is useful as a liquid crystal composition and as a liquid crystal display device that contains the liquid crystal composition. The liquid crystal compound has a large clearing point, large optical anisotropy and sizable or large dielectric anisotropy absolute value under the condition of maintaining a suitable rotary viscosity, enabling the liquid crystal composition that contains the compound represented by general formula F has a large optical anisotropy, small rotational viscosity, high VHR (UV) and long low-temperature storage duration under the condition of maintaining proper clearing point, proper dielectric anisotropy absolute value and proper VHR (initial), and the liquid crystal display device that contains the liquid crystal composition of the present invention has good contrast, high response speed, high reliability and good low-temperature storage stability.

The invention discloses a liquid crystal compound, the structural formula of the liquid crystal compound is as shown in the following formula I, # imgabs0. The liquid crystal compound has high elastic constant K, high dielectric anisotropy delta epsilon, high clearing point Cp, good low-temperature intersolubility, small optical anisotropy delta n and small scattering coefficient; the liquid crystal composition containing the liquid crystal composition has a high elastic constant K, high dielectric anisotropy delta epsilon, a high clearing point Cp, good low-temperature intersolubility, small optical anisotropy delta n and a small scattering coefficient. The liquid crystal composition can be used for developing liquid crystal display elements or liquid crystal displays which have the advantages of high response speed, high contrast ratio, wide display temperature range, good low-temperature intersolubility and good reliability and can effectively improve residual images.

The present invention provides a self-aligning agent and a liquid crystal composition thereof. The liquid crystal composition comprising the self aligning agent of general formula O in the present invention has a lower residue concentration, a smaller roughness, a better alignment effect as well as a better low-temperature storage stability and a better pre-tilt angle stability while maintaining an appropriate clearing point, an appropriate optical anisotropy, an appropriate absolute value of dielectric anisotropy, a larger K value (K11 and K33) and a smaller rotational viscosity.

Provided is a black PDLC dimming film, including a first flexible substrate, a first conductive layer, a polymer liquid crystal layer, a second conductive layer, a second flexible substrate sequentially laminated. The liquid crystal material within the polymer liquid crystal layer includes a polymer doped with liquid crystal molecules and dye molecules with positive dielectric anisotropy Δε. A polarizer is provided in a path of light emitted from the polymer liquid crystal layer, and the structure of the polarizer may be approximated as a filter, which has the effect of select a portion of the light travelling in a specific polarization direction, and block scattered light in other directions. The color of the polarizer itself is gray-black, the combination of the two can change the traditional PDLC dimming film itself matte white is not enough senior effect, so that it is suitable for more high-end application scenarios.

The present invention relates to a liquid crystal (LC) material with negative dielectric anisotropy as defined in claim 1 and its use for optical, electro-optical and electronic purposes, for example in LC displays, in particular energy-saving displays based on the ECB, IPS or FFS effect.

The invention discloses a device and a method for measuring stress in a forming process of a large-size aviation transparent part, and relates to the technical field of polymer injection molding measurement. The device comprises a flexible substrate matched with the surface of a mold cavity, and an interdigital electrode array, a dielectric anisotropy measurement module and a polymer stress calculation module which are arranged on the flexible substrate, the interdigital electrode array is arranged in a non-uniform distribution mode, a high-density arrangement area is arranged in a stress sensitive area, and a sparse array arrangement area is arranged in a non-sensitive area; the module is used for detecting dielectric constants and calculating principal stress differences of different positions. The flexible substrate is utilized to adapt to a complex curved surface, through the non-uniform array design, global coverage of a large-size workpiece is guaranteed, meanwhile, high-resolution capture of a key area is achieved, signal crosstalk caused by global high-density arrangement is effectively avoided, and accurate, lossless and real-time measurement of the forming stress of the large-size aviation transparent part is achieved.

The invention relates to a liquid crystal (LC) material as defined in claim 1, which has a negative dielectric anisotropy, and to the use thereof for optical, electro-optical and electronic purposes, for example for LC displays, in particular energy-saving displays based on the ECB, IPS or FFS effect.

This invention relates to compounds of formula (I), and preferably to liquid crystal media having a nematic phase and negative dielectric anisotropy, comprising a) one or more compounds of formula (I) and b) one or more compounds selected from formulas (II) and (III), wherein the parameters have the meaning given in claim 1, their use in electro-optic displays, particularly in active matrix displays based on VA, ECB, PALC, FFS or IPS effects, displays of this type comprising liquid crystal media, and the use of compounds of formula (I) in stabilizing liquid crystal media comprising one or more compounds of formula (II) and one or more compounds selected from formulas (III-1) to (III-4) and B.

The present invention provides a liquid crystal composition and a liquid crystal display device. The liquid crystal composition comprises at least one compound of general formula I, at least one compound of general formula II and at least one compound of general formula III. The liquid crystal composition provided in the present invention has appropriate optical anisotropy, appropriate clearing point, appropriate absolute value of dielectric anisotropy, larger K value, smaller rotational viscosity, shorter response time, higher transmittance, higher contrast and longer low-temperature storage time. The liquid crystal display device prepared thereby has excellent performance and is suitable for fast response, high contrast VA, IPS, NFFS and other display modes.