DD139867A1 - APPLICATION OF LIQUID CRYSTALS - Google Patents

Abstract

The invention relates to the use of nematic liquid crystals in optoelectronic arrangements for the modulation of continuous or incident light and for the reproduction of numbers, characters and images. The liquid crystals used hitherto have certain disadvantages which consist in too high melting points, too low Klaerpunkten or too low stability against thermal stress, exposure to light, chemicals or electric fields or disturbing self-staining. The aim of the invention are nematic liquid crystals with favorable properties in terms of melting and Klaerpunkt, stability against external influences and colorlessness. It has been found that crystalline-liquid 2,5-disubstituted derivatives of 1,3-dioxane of the general formula are suitable for use in optoelectronic components for the modulation of the transmitted or reflected light and for the reproduction of numbers, characters and images. formula

Description

Application of liquid crystals

the

The invention relates to the application of nematic liquid crystals in optoelectronic arrangements for the module lation of continuous or striking light and to reproduce you numerals, signs and images «

Characteristics of the known technical solutions

Due to their optical and dielectric anisotropy, it is known that in electrochemical liquid crystals different electro-optical effects occur which can be used for the production of optoelectronic components. G Meier, E. Sackmann, J ₀ G. Grabraaier, Applications of Liquid Crystals, Springer - Verlag Berlin-Heid.elberg-New York 197.5; M. Tobias, International Handbook of Liquid Crystal Displays 1975-76, Ovum Ltd. London 1976 /.

Of particular interest are components based on twisted nematic layers, whose twist is reversed under the influence of the electric field and as a result light-dark effects occur. The prerequisite for such components is the use of nematic substances with positive dielectric anisotropy, which can be found on compounds with a strong longitudinal component of the dipole monomer. On substances with negative dielectric anisotropy, the dynamic scattering effect is also suitable for optoelectronic devices. , ,

The "substances hitherto used for optoelectronic components" all have certain disadvantages which consist in too high a melting point or too low clearing point or low stability to thermal stress, exposure to light and chemicals as well as electric fields or a disturbing self-fogging.

goal of

The object of the invention are nematic liquid crystals with favorable properties in terms of melting and clearing point, stability to thermal stress, exposure to light and chemicals and electric fields and colorlessness.

Explanation of the essence of the invention

It has been found that crystalline liquid 2,5-disubstituted derivatives of 1,3-dioxane of the general formula

O-

in which

X =

or X = ίΓ or X «R-.

- and Y «R, and Y = R ³ - <<3) -,

τ> 3

- and Y

- mean.

such as

C _n H _{2n + 1}

»5 ^C n ^H 2n ₊ 1 ^CO ° 5 ^R ~ OCOO; ^c _u H _{2n +} 1s; C _n "

; CN; NO ₂ ; F; Cl; Br; NC-CH * = CH; NC-CH ₂ -CH ₂ ; NC-CH ₂ ;

4-4- 4.

UW J UK J UUUK J UUUUK J

-R ⁴

5. with η = 1 to 10

mean suitable for use in optoelectronic components for the modulation of the transmitted or reflected light and for the reproduction of numbers, characters and images. ·

The substances have relatively low melting points at sufficiently high clearing points, are stable to the action of heat, light, chemicals and electric fields. The substances are particularly advantageously used in mixtures with one another and in mixtures with other crystalline-liquid or non-crystalline liquids Substances The substances with 3 rings have the favorable property of significantly increasing the clearing points of mixtures.

aen to be used for substances according to the invention are contained in the following Tables 1 to 3 *

Mean in ueen tables: K = crystalline-solid, S ^, S _ß = smectic A bzvi "B, N = nematiseh, I" isotropic liquid.

table R ¹ B ¹ · K ² K / \ "\ / - - »5  '· -R ² N • 28.5). i I - 40.5  - HO ^C 7 ^H 15 \ Q / - - * - - - » 25) 53 Verb. ^C 4 ^H 9 C ₃ H ₇ ^S A - 26 29) 40) 50.5 1.1 C ₃ H ₇ O , 107r-109 - - , 5 (. • - (. 22) 35.5). 56 1.2 C ⁴ H ⁹ .'- (. (. 34). 43). 55 1.3 C ₅ H ₄₁ O C ₄ H ₉ «43 (. '- - C · 41) (. 41.5) 56.5). 1.4 ^C 6 ^H 13 ° C ₄ H ₉ , 44 , G.   - - (. (. 45) 48) ill C ₇ H ₁₅ O C ₄ H ₉ , 49 (· - (. 49 .- 35.5). 1.6 C ₉ H ₁₉ O ^0A , 31 (. ~ (. 40-4 - * - 1.7 CN , 45 - 38.5 - 1.8 'C ₅ H ₁₁ 4 ^H 11 , 47 ³ B 34 (. 48) 1.9 C ₃ H ₇ O f \ TT , 42 Sr 45.5 - 1.10 C ₄ H ₉ O C ₅ H ₁₁ , 38 44 50 1.11 C ₅ H ₁₁ O C ₅ H * · 1 # 46 49 1.12 ^C 6 ^H 13 ° C ₅ H ₁₁ , 40 '·. 45 53 1.13 C ₇ H ₁₅ O ^C 5 ^H 11 , 38 50.5. 55 1.14 C ₉ H ₁₉ O ^C 5 ^H 11 , 44 53.5. 56.5 1.15 CN C ₅ H ₁₁ , 45 39) 1.16 C ₃ H ₇ ^e 6 ^H 13 , 48 , ". · ~ 1 * 17 C ₄ H ₉ ^C 6 ^H 13 , 55 40 _s 5) 1.18 ^C 6 ^H 13 ^C 6 ^H 13 , 35 1.19 C ₂ H ₅ O ^C 6 ^H 13 ..32 1.20 C ₃ H ₇ C, H., 6 13 • 36 y 1.2I ₁ C ₄ H ₉ O ^C 6 ^H 13 , 48 1.22 C ₅ H ₁₁ O ^C 6 ^H 13 , 40 1.23 ^C 6 ^H 13 ° ^C 6 ^H 13 , 35, 1.24 C ₇ H ₁₅ ^C 6 ^H 13 , 37 ° 9 ^H 19 ° ^G 6 ^H 13 , 34 1.26 br ^C 6 ^H 13 , 45 1.27 HO ₂ ^C 6 ^H 13 48 1.28 GM C _£ H j. _. 6 13 , 56 1.29 , 56 1.30 , 47

Continued table

Verb S,

1.31 1.32

1.34 1.35

^C 6 ^H 13

CN

^G 6 ^H 13 C ₂ H ₅ O

1.38 Br 1o39 CN

C ₇ H ₁₅ . 49. 59.5 - -

C ₇ H ₁₅ . 37.5. 62 - -

^C A * ". 54 - - (.52)

C ₈ H ₁₇ . 38. 60 - -

C 55). 43. 62

C ₈ H ₁₇ .38 .60. - -

C ₈ H ₁₇ . 48.5 (.44.5) - -

C ₈ H ₁₇ . 60 - - (.51)

C ₈ H ₁₇ . 55 - -

1:42

C ₄ H ₉ COO C ₅ H ₁₁ OCOO

COO

CH ₃ G- (O) -COO

id ± CA, Q- (O) -coo

COO

COO

1.46 NC

± * £ L ^m 2

1_ «48 C ₆ H ₁₅ OC ₇ H ₁₅ . -34 S _B 68 C ₇ H ₁₅ . 27 S _A 30

C ₇ H ₁₅ . 80.5 - -

C ₇ H ₁₅

i5 "

C ₆ H ₁ -

85 - 103 - -

C ₇ H ₁₅ . 113 S _A 166 _S 5

, 143 - -

0 ₂ N »<g) -C00

, 132 - -

42

148.5 193 174

129 p. 182,5. 221

, 159

Table 2: R ⁴ - / ") - ^ - R ³

Vert ». R ⁴ R ⁵ K 44 ⁸ B N I 2.1 2.2 C ₃ H ₇ ^C 6 ^H 13 C ₄ H ₉ OC ₄ H ₉ O • .26 .- 50 ' - '- # •

, -0-.

Table 3: R -O- (-> -

X) - '

Comp. R ¹ : 'R ³ KSS _ß N

3u ^C 6 ^H 13 ° ^C 4 ^H 9 ° * ¹³⁶ ^ * ⁱ²⁴ ^ .166 - -

3 * 2 CN C.HqO. 121 -. - - -. 202.

3.3 CN ^C 6 ^H 13. 83 - - - -. 152.

embodiments

Example 1 5-n-hexyl-2- _i / 4-cyano-phenyl-J7-1,3-dioxane (Compound No. 1.30)

is for optoelectronic devices based on twisted nematic! Layers and shows the following Ί5 characteristics:

Measuring temperature: 35 ⁰ C ·

Threshold voltage: 0.65 V / 50 Hz

Onset time t _E (50 #) »376 ms at U« 1.3 V / 50 Hz

Abk3 ing ing t _A (50 95) = 190 ms, layer thickness 21yüm

Example 2

The substrate Kr. 1 «33 (Table 1) has a strong positive DK anisotropy νοηΛ £ = + 11 at 10 ⁰ C below the apex point.

Claims (1)

He f udans pr u c h 1. substances for optoelectronic components for the modulation of the transmitted or reflected light and for the reproduction of numbers, characters. and pictures, characterized in that crystalline liquid 2,5-disubstituted derivatives of 1,3-dioxane of the general formula -Y where X.sup.R ^-1 - ^)) - and Y = R ² , or X = R ⁴ and Y = R ³ ~ \ ^ / -, or X * ^κ1 ~ @ - ^{un <a Y} = ^r5 · "©" ^meaning and ; R ⁴ - (h) -C00; Bx, NC-CH = CHj NC-CH ₂ -CH ₂ J NC-CH _2; R ^{2 "c} _n ^H 2 _{+ u i} 5 ^0H 5 ° N>^0h4; OCOR ⁴ ; OCOOR ⁴ ; with η - 1 to 10 mean to be used.