The liquid crystal display element is used in various kinds of measuring apparatus, a panel for an automobile, a word processor, an electronic organizer, a printer, a computer, a TV, a clock, an advertising display board and the like including a watch and a calculator. The representative examples of the liquid crystal display method include a TN (twisted nematic) type, an STN (super twisted nematic) type, and a vertical alignment type and an IPS (in-plane switching) type using a TFT (thin film transistor). The liquid crystal composition used in these liquid crystal display elements is required to be stable with respect to external impetuses such as water, air, heat, and light, and to exhibit a liquid crystal phase in as wide temperature range around room temperature as possible, and to have a low viscosity and a low driving voltage. Furthermore, the liquid crystal composition is constituted with several kinds of compounds to several dozens of compounds in order to make dielectric anisotropy (Δ∈) and/or refractive index anisotropy (Δn) optimal values in each display element.
In the vertical alignment (VA) type display, a liquid crystal composition having negative Δ∈ is used, and in horizontal alignment type displays such as the TN type, the STN type, and the IPS (in-plane switching) type, a liquid crystal composition having positive Δ∈ is used. A driving method in which a liquid crystal composition having positive Δ∈ is vertically aligned when no voltage is applied, and a horizontal electric field is applied for display has also been reported, and the need of the liquid crystal composition having positive Δ∈ is further increased. On the other hand, in all the driving methods, a low voltage driving, a high speed response, and a wide operating temperature range are required. That is to say, it is required for Δ∈ to have a positive and high absolute value, for viscosity (η) to be low, and for a nematic phase-isotropic liquid phase transition temperature (Tni) to be high. In addition, it is necessary to adjust Δn of the liquid crystal composition to an appropriate range in accordance with a cell gap by setting Δn×d which is a product of Δn and the cell gap (d). Additionally, in a case where the liquid crystal display element is applied to a TV or the like, the liquid crystal composition is required to have low rotational viscosity (γ1) since a high speed response property matters.
As a constitution of the liquid crystal composition for high speed response, for example, liquid crystal compositions using compounds represented by formula (A-1) or (A-2) which are liquid crystal compounds having positive Δ∈ and liquid crystal compounds (B) of which Δ∈ is neutral in combination are disclosed. Characteristics of these liquid crystal compositions are that the liquid crystal compounds having positive Δ∈ have a —CF2O— structure and the liquid crystal compounds having neutral Δ∈ have an alkenyl group, and these are widely known in the field of the liquid crystal composition. (PTLs 1 to 4)

On the other hand, the application for the liquid crystal display element is expanded, and great changes are seen in the usage method and the manufacturing method thereof. In order to cope with these changes, optimization of characteristics other than fundamental physical property values known in the related art is demanded. That is to say, as the liquid crystal display element which uses the liquid crystal composition, the VA type and the IPS type are widely used, a display element of which the size is also an extra-large size equal to or longer than 50 inches is put into practical use and is used. With the increase in a substrate size, in an injection method of the liquid crystal composition into a substrate, the mainstream type of the injection method has been changed from a vacuum injection method in the related art to a drop injection (ODF: One Drop Fill) method, and the problem in that dropping marks generated when the liquid crystal composition is dropped on a substrate leads to a decrease in display quality became an issue. Furthermore, in the liquid crystal display element manufacturing step by the ODF method, the optimal liquid crystal injection amount needs to be dropped according to the size of the liquid crystal display element. If the injection amount greatly deviates from the optimal value, the balance of the refractive index and the driving electric field of the liquid crystal display element which is designed in advance is lost, and display defects such as generation of spots and poor contrast occur. In particular, in a small-sized liquid crystal display element which is frequently used in smart phones in vogue recently, it is difficult to control deviation from the optimal value to be within a certain range since the optimal liquid crystal injection amount is small. Therefore, in order to maintain a high yield of the liquid crystal display element, for example, effects with respect to rapid pressure change or impact in the dropping apparatus which occurs when the liquid crystal is dropped are required to be small, and performance capable of continuously stably dropping a liquid crystal over a long period of time is also required.
In this manner, in the liquid crystal composition used in an active matrix driving liquid crystal display element driven by a TFT element or the like, while maintaining characteristics and performance required as a liquid crystal display element such as high-speed response performance and the like, in addition to characteristics of having a high specific resistance value or a high voltage holding ratio considered to be important in the related art, and being stable with respect to external impetuses such as light and heat, development taking into consideration the manufacturing method of the liquid crystal display element has been demanded.