JPS63120761A - Coloring material composed of nonionic trisazo compound - Google Patents

Abstract

PURPOSE:To obtain a coloring material composed of a red azo compd., by specifying the positions of a naphthalene ring and a nitrogen atom as a donor of a trisazo compd. and substituents at both terminals. CONSTITUTION:A coloring material is composed of a trisazo compd. of formula I. In the formula, A is a substituted having a Hammett's substituent constant deltap in the range of deltap<=0.55; R1 is H, an alkyl, an alkoxyalkyl, cyano, a halogen- substd. alkyl or an alkylcarbonylalkyl; R2 is an alkyl, an alkoxyalkyl, cyano, a halogen-substd. alkyl, a phenylalkyl, cyclohexyl or phenyl, provided that when R1 is H, there are included the cases where R2 is a group of of formula II or III or a pyroolidine ring; R3, R4 and R5 are each H, F, Cl or methyl. Most of the trisazo compds. have a stick structure, exhibits good dichroism in liquid crystals and films and can be used as a coloring material for liquid crystals, polarizing films, etc., and a dichromatic material.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a coloring material made of a nonionic trisazo compound, which is useful as a coloring material for color liquid crystals, polarizing plates, and the like.

Prior Art The usefulness of nonionic trisazo compounds as colorants for liquid crystals is disclosed in Japanese Patent Application Laid-open Nos. 56-57850 and 58-8.
It is publicly known as No. 4858. Among these trisazo compounds, compounds having a naphthalene ring in the azo skeleton and a structure in which a nitrogen atom is crystallized at the para position of the azo group in the terminal benzene ring (hereinafter referred to as basic structure) have the same substituent. Compared to disazo compounds, which have absorption in a longer wavelength region, they have a color tone ranging from purple to blue in liquid crystals, and red trisazo compounds, which have a color tone ranging from reddish-orange to reddish-purple, have not yet been developed. Not proposed. On the other hand, in order to easily impart a red color to disazo dyes, various red dyes have been proposed by modifying their structures.

Problems to be Solved by the Present Invention The present inventors, unlike the development direction of trying to obtain a red compound using a disazo dye, focused on a trisazo compound and developed a coloring material made of a red azo compound having such a structure. This is what we intend to provide.

Means for Solving the Problems In order to achieve the above object, the present inventors focused on the trisazo compound having the above-mentioned basic skeleton structure, and as a result of various studies, found that in this structure, the naphthalene ring and the donor nitrogen By identifying the position of the atom, identifying the substituents at both ends, and identifying the molecular structure as a result, we discovered the desired red coloring material made of a nonionic trisazo compound and completed the present invention.

This invention relates to a colored material made of a trisazo compound represented by: In the above formula, A has a Hammett substituent constant σp≦0.
It is an aprotic substituent in the range of 55, and the substituent in this range is triph? fluoromethyl group: halogen; A is φ-C-0- or φ
-0-C- (φ represents an alkyl group or an aryl group which may have a substituent); an alkyloxycarbonyloxy group; an alkyl group;
Alkoxy group; alkoxyalkyl group; alkoxyalkoxy group; arylalkyl group, alkoxy group which may have a substituent at position 4; cycloalkylalkyl group, alkoxy group which may have a substituent at position 4; Examples thereof include an aryl group or a cycloalkyl group such as a phenyl group, a biphenyl group, a cycloalkyl group, and a cycloalkylphenyl group, which may have a substituent. Ro is hydrogen: an alkyl group such as a methyl group, ethyl group, pentyl group, or octyl group; an alkoxyalkyl group having an alkoxy group such as a methoxy group or an ethoxy group; an alkyl group substituted with halogen or a cyano group; or an alkyl group as described above. This includes cases in which it represents an alkylcarbonylone ring. R2 is an alkyl group defined as R□; an alkoxyalkyl group; an arylalkyl group or a cyclohexyl group that may have a substituent such as an alkyl group, an alkoxy group, or a halogen at the 4-position; 4
Represents a phenyl group which may have a substituent such as an alkyl group, an alkoxy group, or a halogen at the position.

The trisazo compound of the present invention can be prepared by
The crude azo compound obtained through the following steps is purified to a practical level by column chromatography, recrystallization, etc., and then used.

Effect Because the nonionic trisazo compound used in the present invention has a specific structure, it causes a short wavelength shift of about 20 nm compared to conventionally known similar trisazo compounds, and has a reddish color ranging from reddish-orange to reddish-purple. It becomes an azo dye, and when used, it becomes a red coloring material. Many of these compounds have a rod-like structure and exhibit good dichroism in liquid crystals and films, and can be used as coloring materials for liquid crystals, dichroic materials, coloring materials for polarizing films, etc.

Next, the present invention will be explained with reference to Examples.

Example 1 (Synthesis of present invention compound No. 1) 4-(4-(
2.1 g of 4-butylphenylazo)-1-naphthylazocoaniline was added to 30 ml of acetic acid. 0.35 sodium nitrite dispersed in 10+il of propionic acid at 5-7°C under stirring.
An aqueous solution containing g was added dropwise to diazotize the mixture for about 1 hour, and to this system was added 4 parts of an acetic acid solution containing 0.9 g of N,N-diethylaniline, and the mixture was reacted at the same temperature for about 2 hours. After the reaction, the reaction solution is transferred to methanol, and the resulting crystals are filtered off and dried. This product was purified using a silica gel column and recrystallized from ethyl #acid. This one has the following structure, λta
527 nm (chloroform), wr, p, (melting point) 189°C.

GR-41 (biphenyl mixed liquid crystal) λm 549
nm.

Order parameter (S value) indicates 0°76.

λtm　527nm Known compound λm550n For comparison, λm of a known compound is listed (chloroform).

Example 2 (Synthesis of Inventive Compound No. 2) In Example 1, N,N-dimethylaniline was used instead of N,N-diethylaniline, and the reaction and treatment were carried out in the same manner as in Example 1 to obtain Inventive Compound No. 2. is obtained. In this general formula, A is C4++9. R□=R2=CH3,R
3=R4=R5=H and λm (chloroform)
515 n+s, m, p, 6λtn indicating 209℃
538 na+ (GR-41), S = 0.7
8 is shown.

Example 3 (Synthesis of the present compound N003) 4- (4-
Dissolve (4-chlorophenylazo)-1-naphthylazo]aniline in 10+ml of DMF.

The mixture was added to 40 ml of acetic acid and dispersed, and diazotized for about 30 minutes by adding an aqueous solution containing 0.2 g of sodium nitrite at 5 to 7° C. while stirring. In this system, N,N-diethylaniline 0.77
Add 1 to 3 g of acetic acid solution and react for about 2 hours, then pour the reaction solution into methanol, collect the resulting crystals by filtration, and dry. This crude product was purified by silica gel column and recrystallized from ethyl acetate. This one' has the following structure, and λ
Nada 531 stop (chloroform), m, p, 204℃
shows. For comparison, λm of known compounds is listed.

Known compound λva 553n+* Example 4 (Synthesis of present invention compound N004) By using trifluoromethyl in place of chloro in Example 3,
Compound N094 of the present invention is obtained by the same reaction and treatment. In the general formula, A = CF1. R1
=l(2=C2H9,R,=R,=R,=H, and λ
rrr 534 nm, (chloroform), a+, p,
For comparison, known compounds showing a temperature of 209°C are shown below.

Known Compound λtx 556N LayerOther compounds used in the present invention are synthesized in the same manner.6 Representative examples thereof are listed in Table 1.

■--Each person l nu Et Et
HHII2 Bu Me
Me If HII3
CI Et Et
If HII4 CF,
Et Et HHII50uMeM
eHHMe 611uQ Et Et H11I7 A
(Et Et HHII8 nu M
e CIIQCI HHII9 Bu M
e C1<ΣCI HII 呵e+01dD-C
Near Bu Bu HIt III
A5 Bu Decyl H)l II
+2 0uOEt Et t
l HItIs Bu HA++
II H5,6-benzo16
Bu HCHQ-＾-)1 )1 5
．． 6-benzo17 Bu' HC straight 4h
sHH5,6-benzo18Bu
HCH luck y()^a+HH'5.6-pyrido19
Bu Me CIIQ Htl lI2
0 A-kai Cl(,OEt 01.Cll□CN
11 II I+ In the above table, Me is a methyl group,
Et is an ethyl group.

U represents a butyl group, ^ represents an aluminum group, and ■ represents a trans-cyclohexane ring.

The S value was calculated using the following formula: 5=D-1/D+2. Here, D represents the dichroic ratio, and the absorbance is measured when a host liquid crystal containing 1 wt% of a compound is sealed in a homogeneously oriented 8 μm thick cell, and when linearly polarized light is incident parallel to the alignment direction and when it is perpendicular to the alignment direction. It was determined by the ratio. In this case, the influence of absorption by the host liquid crystal and glass cell was corrected.

The nonionic trisazo compound used in the present invention has an intramolecular charge transfer type color-forming structure, and the larger the electron-attracting power of substituent A, the longer the wavelength of λm shifts. Hammett's substituent constant σp corresponds to this electron-withdrawing force, and as σp increases, λI shifts to longer wavelengths. When σp exceeds 0.55, λ1 exceeds 540 nm in chloroform and exceeds 560 IIn in liquid crystal (biphenyl liquid crystal), which does not result in the red color targeted by the present invention.

Effect The coloring material made of a nonionic trisazo compound according to the present invention uses a trisazo compound having a specific structure,
It is a red pigment ranging from reddish-orange to reddish-purple, and has a rod-like structure, and is useful as a coloring agent for liquid crystals, a dichroic material, a dichroic material for polarizing films, etc. The liquid crystal may be of any type such as nematic, smectic, or cholesteric-nematic phase transition type, and may have either positive or negative dielectric anisotropy or may exhibit ferroelectricity. As the polarizing plate film, any commonly used film such as polyvinyl alcohol and polyethylene terephthalate may be used.

Procedure h ■ Formal document (method) February 2, 2019 (1) Display of the case Patent Application No. 266440 of 1988 3 Person making the amendment Relationship to the case Patent applicant (however, date of sending of the notice of amendment order) ) 5 Subject of amendment Application and specification 6 Content of amendment Correspondence and engraving of specification/attached sheet (no change in content)

Claims (1)

[Claims] General formula (I) ▲Mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, A is Hammett's substituent constant σP≦0.5
5, R_1 represents hydrogen; an alkyl group; an alkoxyalkyl group; a cyano group or a halogen-substituted alkyl group; or an alkylcarbonyloxyalkyl group; R_2 represents an alkyl group; an alkoxyalkyl group; a cyano group or Represents a halogen-substituted alkyl group; a phenylalkyl group that may have a substituent; a cyclohexyl group that may have a substituent; or a phenyl group that may have a substituent, and when R_1 is hydrogen, the formula is ▲ , there are chemical formulas, tables, etc. ▼ means ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼, and ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼ represents a pyrrolidine ring. including. R_3, R_4, and R_5 represent hydrogen, fluoride, chloro atom, or methyl group. ) A coloring material consisting of a trisazo compound.