JPS58142961A - Liquid crystal composition - Google Patents

Abstract

PURPOSE:To provide a liquid crystal composition containing specific ester compounds and a chiral nematic liquid crystal at specific ratios, exhibiting quick responce even at a low voltage, having broad temperature and voltage margins and high chemical stability, and suitable for a liquid crystal light valve of a printer. CONSTITUTION:The objective composition is composed of (A) a mixture of ester compounds comprising 40-60wt% compound of formulaI(R and R' are 1-8C straight-chain alkyl), 0-20wt% compound of formula II, 0-20wt% compound of formula III, 5-20wt% compound of formula IV and 0-15wt% compound of formula V and (B) 0-5wt% chiral nematic liquid crystal. A liquid crystal panel suitable as a liquid crystal light valve for the optical ON-OFF control can be manufactured by inserting the liquid crystal composition between a pair of oppositely placed glass plates each having a NESA electrode at the inner side. The ON-OFF control can be carried out by applying a signal containing a component having higher frequency than the cross frequency (fc) of the liquid crystal material and a signal containing lower frequency component than fc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is characterized in that when a signal with a frequency component of fc of a liquid crystal material held between a crystal panel and a signal with a frequency component higher than fc is applied, This invention relates to liquid crystal light pulp that performs control. IIKSpecifically, by using a new liquid crystal composition, the liquid crystal light pulp K11l has a very high light response speed for mosquito panels.

There is rapid progress in entertainment, increased capacity for information processing, faster calculations, and the popularization of zero-shift (office automation) devices. For printers, which are one of the terminals installed at 0^, the membership fee is high speed, good print quality, and low price for IIK, but currently there are few products on the market that satisfy these requirements. As soon as you come out, you are strongly desired to be a 10th grader.

Printing l5fI (lIII Kaisho 56-9556
81 has reached the level of merit in the points mentioned above and is attracting attention.

First 1. A memorandum m is printed on the photosensitive drum 102 by the nine-light signal generating section 101 using the liquid crystal light pulp, as shown in No. 111, which shows the configuration of the liquid crystal light pulp type printing** described above. At this time, the photosensitive drum 102 is charged in advance by a corona charger 110. Mitsushin 4 at this time
4F1 Normally, when printing one piece of literature, light is generated corresponding to one character. As a result, an electrostatic latent layer is formed, and the toner is developed with a magnetic brush developer *5103. The developing method at this time is usually one reversal development. Through this tube, the toner is transferred onto plain paper 104 and fixed by a fuser 106. The toner remaining on the photosensitive drum of the transfer film is removed by a plate V 108, and the charge is removed by an electrostatic **Fi charge removal lamp 109, and the process ends.

FIG. 2 shows the configuration of the optical signal generator. The light emitted from the light 11201 is subjected to ONO control in the liquid crystal panel section (211 to 218), and the transmitted light is transmitted through the condensing lens 221 to the front plate 2.
11, formed on the glass plate 212 by KIIK coating, sputtering, dipping, etc., and KVt photoetching. A liquid crystal 218 is sandwiched between an alignment control film 216, a seal 217, and a liquid crystal panel.

s1m is an IFrIB diagram of the liquid crystal panel, with a group of micro shutters 302 that transmit light ms and a constant light
It is more powerful than the optical mask section 301 that performs IF+.

Next, the driving principle of liquid crystal light pulp will be explained.

No. 411 shows signals applied to the liquid crystal panel and transmitted light characteristics. However, what is shown here is the case of single dynamo drive. When the liquid crystals K and fc have high frequency components, and 4# is applied during the opening period, the 4th
II &)), the panel transmits light [No. 411
g)) mth LCD K signal with a lower frequency component than fg! When 10 times are applied (Fig. 4 Jl)) the panel will layer the light, the a is the selection period Ih #) In this case, the O de Feng T will be the V Te island, and it is applied like this. The P-directed brightness of liquid crystal molecules can be controlled by the frequency of the signal.
This phenomenon is known by NK, and although the details thereof will be omitted, this phenomenon is based on the property that the sign of the dielectric anisotropy of the liquid crystal is inverted depending on the frequency of the applied signal. It shows the frequency dependence of the dielectric constant a# in the long axis direction and the dielectric constant - in the short axis direction of the 511th #i liquid crystal molecule. Crossing frequency fc (##=-
The sign of the dielectric anisotropy Δ1 is reversed across the frequency (frequency).

As mentioned above, if the liquid crystal light pulp is driven by 1%, if the liquid crystal light pulp is used for the optical writing part KNA%A of the printing capacity, the printing capacity will be high speed, the printing quality will be high, the WK
In order to achieve high reliability, many constraint conditions must be met. In order to satisfy this requirement, it is of course possible to improve the characteristics to some extent by changing the light source optical system around the panel and the drive system, but the basic % of the liquid crystal. A lot depends on gender.

Excellent liquid crystal light pulp for writing and liquid crystal material Kl
Item 1 is listed below as the basic characteristics required.

t High-speed response with low voltage.

2. 11 degrees - wide voltage margin.

This is done by ensuring high credibility.

Liquid crystal materials for two-frequency drive have been researched by Junto at Display Komisaki, and excellent products have appeared, but printing! Extremely fast response (1
4, which requires 149 seconds or less), has not yet been studied, and liquid crystal materials that satisfy all of the above-mentioned percentages are not well known. This is a liquid crystal material for liquid crystal light pulp with improved characteristics.
The purpose is to respond quickly at 1g voltage.

2. Once, the voltage margin is wide.

l　To be examined with a high level of credibility.

The goal is to provide a liquid crystal material for dual-frequency driving that satisfies the above requirements.

Below V, I will further explain the ``required term @''.

t High-speed response with low voltage.

Drive circuit KXC is used to reduce the size of the finished product and reduce image cost.
When Q is used, the upper order of the drive voltage and drive frequency is constrained. In order to reduce WK power consumption, low voltage and low frequency are desirable.The response speed of liquid crystal is rumored to be T. As shown in "C", rounding that is inversely proportional to the square of dielectric anisotropy, INK, is necessary to obtain a high-speed response. Increase the absolute value of dielectric anisotropy at the driving frequency
It is necessary to Low viscosity is also required.

The WK driving frequency must be extremely high, and f6 at the operating temperature must be extremely low.There is no liquid crystal material that satisfies these requirements with a single component. The goal is to satisfy each characteristic in a well-balanced manner. First, fe and viscosity are adjusted, but these two have contradictory properties. o* [*Dashi, R,]II
' is 1~R-@-@-a o o -@-R'
It has the property of having 8 carbon atoms and 1.

Next, the components that eIF the dielectric anisotropy at low frequencies,
It is a component that increases dielectric and electric ascent properties at high frequencies, but fake liquid crystals or compounds with a molecular structure similar to liquid crystals with a large positive 0 dielectric anisotropy fl have a large absolute value. There are many, but there are very few turtles with a large absolute value of negative dielectric anisotropy. In KFi, -, the melting entropy is negligible, the liquid crystal temperature is wide, and furthermore, fc, the restriction of the cape that does not have a negative effect on the character is added, and the variety is even more @! The alkyl 1 * in the components of the composition provided by the present invention has a very large positive 0III electric anisotropy, and also has an excellent compatibility with the gtS component. ing.

Furthermore, among the components of the sawtooth compound, the absolute value of the negative dielectric anisotropy is large and the compatibility with other components is excellent.

Next, regarding the powerful chiral nematic liquid crystal with lIr+ component provided by this company, in the case of display panels, a trace amount of scissors component is added to prevent reverse tilt, and KN liquid crystal for guest host display is used. There are many known examples of using the memory effect of liquid crystals with added components to improve contrast. It is well known that the response speed can be improved by utilizing the helical force of the chiral nematic liquid crystal, that is, the force of returning to the spiral structure. The method has the same effect as mentioned above, and the speed change of 1g5 is also effective. In the two-cycle driving method, driving is based on a signal having a high frequency component as high as s/', that is, Il
1 [When crystal molecules are made into a square V meat with cell 2, there is an effect of connecting the speed to the side dish.

The present inventor, Misaki, has discovered that by combining the above-mentioned components in an appropriate ratio, the absolute values of Δ@b and Δam (#I) cannot be reduced to the absolute value of ΔC in conventional compositions. By adding chiral nematic liquid crystal, we were able to significantly increase the response speed at operating temperature and voltage.

In the case of a single-component liquid crystal, it is expected that the interaction between different components, which is different from that of a single component, will have a considerable influence on the viscosity, fas, and ultimately the response speed. Even in the composition provided by #4, it seems that this interaction is working in the direction of the sacramental pope as a composition. Doji-mechanical interpretation is expected from the research of Imahotara.

The above is the reason why the component according to the present invention is used to change the characteristic t to fs.

2. Wide temperature and voltage margins.

First, regarding the temperature llF merge ν, the dependence of the electric ascension of the Wl crystal on the m liaison is shown in Fig. 6, Δ-Ll
Dielectric anisotropy at i low 11# low part 1# wave number, Δam is dielectric anisotropy at high driving frequency. As can be seen from Figure 0, Δε decreases rapidly as the temperature increases. This slope Il'lF1 Although there are some differences depending on the liquid crystal, it is a basic characteristic of the liquid crystal, so when using the actual IIK, #'
If a temperature change region with a small amount of temperature change on the shoulders of i and Δ6 is selected, as in the case of the present invention, if a very continuous response is required, ν will be The fee is to lower the viscosity of liquid crystal and use it. Like this II! 11! Based on the fact that it is undeniable that Δl will move to some extent due to condensation, and in order to obtain a wide l1lWl margin, we will adopt the range in which the party transparency of Il crystal is saturated. That is the membership fee. In other words, this is based on the premise that under a constant voltage, the response is continuous and the light transmission weight is saturated, which satisfies the above-mentioned 4I property 1. In addition, the voltage margin can be considered in the same way, and 61°5 reliability can be ensured.

Many studies and 11 experiments have been conducted regarding the chemical, optical, and electrochemical stability of liquid crystals. All of the liquid crystals according to the present invention are ester-based liquid crystals, and have high optical reliability, and due to accelerated aging, the reliability has been evaluated to be at a practical level.

In order to satisfy the above-mentioned characteristics 1.2゜3 in a well-balanced manner and at a performance level, the present invention leaves the proportions of the above-mentioned components as a composition.
114! The goal was to create nine outstanding liquid crystal materials. That is, it is a composition as shown in No. 111.

[However, in the above FlI, R, fl'tj Iwao atoms are 1 to 1
Table 1 The details of the present invention will be explained with reference to examples.

EXAMPLE A 2KW gelatinous liquid crystal composition was prepared and its basic properties and light transmission properties were investigated.

12 [The ``Chilllff'' in the front has the structure of ``Hot■''] 711th Kl! 2 shows the frequency dependence of the dielectric constant of the liquid crystal composition, and the constant temperature change is 30°C.

Insert this liquid crystal into a test cell with a thickness of L6smt1,
Low frequency signal (isOV, 111g), high frequency signal 44<
Around the time I performed H dynamic drive with SOV, 1iSOKIIg), I was 80th! It showed excellent light transmittance.

■Yo11. In M dynamic drive, the repetition period l
t it ~16 mmg, -0 o'clock @ (L S ~a
A repeat response is possible in 4 m5ec. However, the rubbing angle of the cell used at this time was 80 @, and the light directions of the polarizing plates sandwiching the cell were at right angles to each other. Measurement - 40 Liao
It was ℃.

Next, a printing experiment was conducted using this liquid crystal light pulp. The liquid crystal cell used was the same as #1 described above, the driving conditions were also the same, and the light source had the structural formula Ov Mg A4t.
Ot・: A high-intensity fluorescent lamp using a fluorometer,
Sensitize with photoreceptor KtjT- and use 98-.

As shown in FIG.
The one-plane movement speed jet was 5 exit's #e, and when I drove the liquid crystal light pulse and performed optical writing,
Corresponding to the 0N-OF7, it is possible to form a clear image.This embodiment is an example of the use of the liquid crystal light pulp swept by the present invention, and it is possible to form a clear image. It is also applicable to writing phonographs and displaying capes.

In addition, the skin liquid crystal M paraboloid used in this example is an example, and even if each component is replaced with its homologue K11, the blending ratio is also determined from the excellent characteristics shown in the table described in the claims. The present invention is not limited to this embodiment, since the present inventor has already tried to realize it.

As mentioned above, the present invention utilizes the dielectric dispersion of liquid crystal,
He succeeded in improving the responsiveness of the liquid crystal material in the liquid crystal light pulp that performs high-speed switching by using two-horse wave drive, and in practical use, the writing lambda of this printing at, temperature and voltage margin characteristics. The effects of the present invention are significant because of the fact that this can be summed up in a nutshell.

[Brief explanation of drawings]

FIG. 1 is a structural diagram of a liquid crystal light pulp type printing device. FIG. 2 is a schematic diagram of liquid crystal light pulp. This is the upper mrta of the liquid crystal panel used for the 5th IllFi liquid crystal light pulp. The 4th m is the signal applied to the liquid crystal Ride Pulg and the optical response at that time. The 5th m is the frequency 1/ll4I property of the dielectric constant of the liquid crystal. The 6th WJ is a characteristic of dielectric anisotropy of liquid crystal. Number 711 is the frequency aS characteristic of the dielectric constant of the liquid crystal condensed eyelid used in this example. FIG. 8 shows the capital response characteristics of the liquid crystal light pulp according to this example. Applicant Co., Ltd. - Sukeiseikokin No. 1 Item 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] Two glass plates having Nesa Den No. 11 inside facing each other,
A signal having a frequency component higher than the cross frequency (hereinafter abbreviated as FE) of the liquid crystal material and a signal having a frequency component lower than s FE are applied to the liquid crystal material with the liquid crystal material sandwiched between them, either singly or in a superimposed manner. In the liquid crystal light modulation fi# which controls the strong sound of the transmitted light by Shows chain full kill]