DD284893A5 - CRYSTALLINE-LIQUID SUBSTANCES - Google Patents

Abstract

The invention relates to novel crystalline liquid substances for optoelectronic components for modulation of the incident or transmitted light and for the representation of numerals, characters and images. The aim of the invention are mixtures with crystalline-liquid properties, which are characterized by stability, favorable electro-optical properties and favorable temperature ranges. The object of the invention is to find new components with favorable properties for the mixtures to be used. According to the invention, new crystalline liquids of the general formula I, {liquid crystals; nematic; smectic; Electro-optics; displays; ferroelectric; Multiplex properties; substituted propancarboxylic acid esters}

Description

Field of application of the invention

The equation relates to new crystalline liquid substances for optoelectronic components for modulation of the incident or continuous light and for the representation of numbers, characters and images. Components of this type are used in electronic watches, computers and other devices.

Characteristic of the known solutions

A large number of crystalline liquid substances are already known (D. Demus, H. Demus, H. Zaschke: Liquid Crystals in Tables, VEB Deutscher Verlag für Grundstoffindustrie Leipzig 1974, D. Demus, H. Zaschke: Liquid Crystals in Tables M ₁ VEB German publishing house for raw materials industry Leipzig 1984, H. Kelker, R. Hatz: Hand book of liquid Crystals, publishing house chemistry Weinheim 1980). For use in optoelectronic devices, many substances have been proposed, but there is no single substance, which even approximately meets the requirements of practice. Therefore, only mixtures for optoelectronic components are used. In order to adapt the mixtures to specific requirements, it is necessary to have individual components with very different properties, so that the search for new suitable substances is constantly continued.

Mixtures with nematic properties are needed for a larger number of different types of display (E. Kaneko: Liquid Crystal TV Displays: Principles and Applicatins of Liquid Crystal Displays, KTK Scientific Publ. Tokyo 1987). Substances with ferroelectric smectic C phases are required for fast switching displays (N.A. Clark, S. T. Lagerwall: Appl. Phys. Lett., 36, 899 [1980], US 4,367,924). Above all, there is still a need for stable substances which have chiral or non-chiral smectic C phases in favorable temperature ranges

 It has already been proposed (DD WP 155063 and 155078), substances of the general formula

° ^H 2n + 1

з-СНр-СОО

with ring A = 1,4-phenylene or 1,4-cyclohexylene in optoelectronic arrangements. The <e substances show exclusively nematic properties.

It has also been proposed (WO 87/05291 C69 / 90), substances of the general formula

where the rings A, B, C can also be 1,4-phenylene or 1,4-cyclohexylene and m = 1, 2 or 3, to be used in optoelectronic components. The chiral or non-chiral substances may have nematic and smectic phases. There is also the proposal (EP 0104327), substances of the general formula

with Q ¹ , Q ² = 1,4-phenylene, 1,4-cyclohexylene and various other ring systomes,

m = 1 to 6, η = 0.1, p = 0 to 5

to be used as crystalline-liquid dielectrics.

The patent does not contain any concrete description of the invention, in particular it has not been proven that the substances of the general formula are crystalline-liquid, nor what types of crystalline-liquid phases (nematic, smectic) can occur. Also, the usability of the substances whose general formula has a very broad claim as dielectrics has not been established.

Object of the invention

The aim of the invention are mixtures with crystalline-liquid properties, which are characterized by stability, favorable electro-optical properties and favorable temperature ranges.

Explanation of the essence of the invention

The object of the invention is to find new components with favorable properties for the mixtures to be used. According to the invention, new crystalline liquid substances of the general formula

R'-Q'-CHj-CHi-COO-a'-M-toVR ²

in which

M = -COO-, -OOC-, -N = N-, single bond R ¹ = C "H ₂ n +! - mitn = 2 to 12

R ^J = -C _m H _{2 m +} i, -OC _m H _2m + i (chiralodernichtchiral), - CNmitm = a = Ocderi,

used as components for crystalline-liquid mixtures.

The new compounds are chemically stable and thermally stable, sometimes have very favorable state ranges of the crystalline liquid phases and are readily soluble in all conventional thermotropic liquid crystals and their mixtures. It is surprising that many of the substances according to the invention have relatively broad domains of the smectic C phase, which possess ferroelectric properties due to chiral properties of the substances according to the invention or chiral additives. In particular, it is surprising that the substances according to the invention in optoelectronic components with nematic mixtures significantly improve the multiplex ratio

 The preparation of the new substances is carried out according to known methods (Houben-Weyl, Vol. VIII pp. 359ff.).

AuBfuhningslMtepM · example 1

Examples of the substances according to the invention are given in the following Tables 1-6 ». As it turns out, many of the substances are nematic with favorable domains of existence. Other substances have chiral or non-chiral smectic C phases.

Where:

K = crystalline-solid N = nematic Sa, S _b , S _c = smectic phase of type A, B, CI = isotropic-liquid The numbers between the phase names mean transformation temperatures in ° C. Brackets indicate monotropic phases.

Table 1

Substr. No.

° п ^Н 2п ₊ Г <О

V-CH ₂ -CH ₂ -COO

Transformation temperatures [ ⁰ C]

1.1 2 C ₄ H ₈ K119N132I

1.2 2 C ₇ H ₁ B K78N112I

1.3 4 C ₆ H ₁₃ K82S _C 92N115

1.4 4 C ₇ H ₁₆ K70S _c 93S _A 98N113l

1.5 6 C ^ H ₁ K85 Sc 98 S _A 108 N1141

Subst. No. 1.4 Sc -> S _x 59 ° C and 1.5 S _c -> S _x 78 ⁰ C; Texture image of S _x in the polarizing microscope points to S _B. Table 2

N. η R A Transformation temperatures [ ⁰ C] No. 2.1 2 CeHn H K77N133I 2.2 3 C ₇ H ₁ B H K65S _c 88S _A 101N132l 2.3 ¹¹ 4 CbH ₁₁ H K74S _A 129N156I 2.4 4 C ₆ H ₁₃ H K62S _C 83S _A 127N152I 2.5 4 C ₇ H ₁ B H K50S _c 92S _A 112N135l 2.6 4 C ₈ H ₁₇ CH ₃ K48N95I 2.7 6 CH ₃ H K94N120I 2.8 6 C ₇ H ₁ B H K52S _B 82S _c 110S _A 122l 2.9 6 C ₈ H ₁₇ H K56S _B 83S _C 113S _A 124I

1) Additional conversion: Sc - »Sx at 64 ° C. Texture indicates a Se phase in a polarizing microscope.

Tatolle 3

Noun. N

Table 5

4 4

3.6 6

Table 4

• 98

• 73

• 50 • 109

• 98

• 85

• 108

Substr. η m I K sc N I No. 4.1 3 6 O • 112 • - • 126 • 4.2 4 6 0 • 111 • - • 125 • 4.3 6 6 0 • 63 • - • 90.5 • 4.4 6 8th 1 • 89 • (80) • 114 •

• 156 • 104 • 114 • 120 • 110 • 109

N. η K119 conversion Tempen No. K124 5.1 2 K122 (S _X 117) S _C 125CH221I 5.2 3 K116 S _x 137 Sc 145 CH 2451 5.3 4 Sc 141 CH 2371 5.4 6 S _x 122 Sr 149 CH 2251

Texture shows a mosaic-like structure similar to S _B in a polarizing microscope

Table 6

K83 S _x 105Sc112S _A 140l

K90 (S _x 80) S ₀ 219 N 2531

Example 2 Shear viscosities were measured on some substances. The following values resulted:

Substance viscosity η [cP] No.

2.1 56.1

2.6 71.3

Example 3 The mixture A has the following composition molar fraction in%

5n-Propyl-2- [4-cyanophenyl] -1,3-dioxane 35,3

5n-pentyl-2- [4-cyanophenyl] -1,3-dioxane 35.3

5n-Hexyl-2- [4-n <-hexyloxyphenyl] -pyrimidine 8.1

5n-hexyl-2- [4-n-nonyloxyphenyl] -pyrimidine 3.7

4-N-butyl-cyclohexanecarboxylic acid 4-ethyloxyphenyl ester 11,4

4-n-hexylcyclohexanecarboxylic acid 4-ethyloxyphenyl ester 6,2

This mixture A and mixtures of A and inventive substances were twisted in electro-optical cells Orientation (Schadt-Helfrich cell) examined. The following measured values resulted: MiA Substance No. T _n , U ₀ E ⁶⁰ A ⁶⁰ N _m "

[mol%] lmol-%] [ ⁰ C] IV) [msl [ms]

100 - - 48.5 1.1 140 60

90 1.2 10 55.5 1.3 500 170

90 1.4 10 56.5 1.4 300 120

90 3.4 10 60.5 1.4 300 120

Operating voltage for switch-on time τ _Ε is U = 2 x U ₀ switch-off time τ _Α (each with 50% intensity change) Temperature: 20 [ ⁰ C] Layer thickness d = ЮЮt Frequency: 500Hz

Multiplex degree N _m . "= {} ^{2 mitp}

U ₁₀

U, o; Um - voltage at 10% or 50% intensity change Even by relatively small additions of the substances according to the invention, the multiplexing levels are considerably increased, which is for

the application in all displays with multiplex control gives a big advantage.

BeispieU

The mixture B has the following composition

5n-Hexyl-2- [4-n-hexyloxyphenyl] -pyrimidine 68.5

5n-hexyl-2- [4-n-nonyloxyphenyl] -pyrimidine 31.5

The mixture B and mixtures of B and substances according to the invention were investigated in electrooptical cells in a twisted orientation (Schadt-Helfrich cell). The following measured values result:

MiB Substance No. T _n , U 'E ⁶⁰ A ⁶⁰ N _m " lmol-% 1 Imol-% 1 [" Cl [Vl [msl | msl

100 - - 60,0 5,0 180 60

90 2.7 10 61.0 5.7 250 84

90 3.4 10 65.5 5.5 240 60

Temperature: 40 ° C Frequency: 500Hz Even the addition of lesser amounts of compounds of the invention to nematic mixtures increases the degree of multiplexing

considerably.

-6- 264

Example 5

The substances with smectic C phases can be added to other substances or mixtures with C phases and increase the range of existence to higher and lower temperatures.

Mole fraction in%

5n-octyloxy-2 (4n-butyloxyphenyl) -pyrimidine 11,46

5n-octyloxy-2 (4n-hexyloxyphenyl!) Pyrimidine 17.00 5n-octyloxy-2 (4n-octyloxyphenyl) -pyrimidine 3.11

5n-octyloxy-2 (4n-decyloxyphenyl) -pyrimidine 3.25

5n-octyloxy-2 (4n-dodecylphenyl) -pyrimidine 2.17

5n-octyl-2 (4n-hexyl-cxyphenyl) -pyrimidine 23.02

5n-octyl-2 (4n-octyloxyphenyl) -pyr! '' Idin 12,46 5n-octyl-2 (4n-decyloxyphenyl) -pyrimidine 7.53

Substance no. 2.5 20.00 according to the invention Conversion temperatures: K -2 Sc 48.5 Sa 62 N 841

Examples

Mole fraction in%

8 components like example 5

Substance no. 1.3 20 according to the invention

Conversion temperatures: K 3 Sq 53 Sa 63 N 811

Claims (1)

Claim: Crystalline liquid substances for optoelectronic components for modulating the incident or transmitted light and for displaying numerals, characters and images, characterized in that new crystalline liquid substances of the general formula • о M = -COO-, -OOC-, -N = N-, single bond R ¹ = C _n H ₂ n + i-mitn = 2 to 12 R ² = -CmH2m + i - »- OC _m H2 _{m + 1} 0- (chiralodernichtchif! B-CNmitm = a = O or 1 mean, be used as components for krisiallin-liquid mixtures.