CA1064858A - Color-changing indoline-heterocyclic compounds - Google Patents

Abstract

Abstract of the Disclosure The invention relates to apparatus for containing color changing compounds. The compounds are represented by the formula:

Description

~06~S~

Background of the Invention Spiropyran compounds have been well known as substances which change, lose or restore their colors. ;~
However, the abovementioned known substances have such shortcomings as requiring large amounts of energy for sti~ulation and having poor stability. ~:
According to the invention there is provided an apparatus comprising a pair of electrodes, which are arranged with a sui'cable gap inbetween and at least one of which is transparent, and an insulating spacer, which together with the electrodes constitute a cell containing ; -~
the solution of a color changing compound, having the ~ :`
belowmentioned chemical formula~

~ ~ _ z . . -wherein Q represents a benzene ring with or without a second fused benzene ring and/or at least one ring sub-stituent selected from the group consisting of lower alkyl, lower alkoxy, halogen, carboxy, carboalkoxy, nitro, non-substituted-amino, mono-alkyl substituted amino, 20 di-alkyl substituted-amino, substituted-phenyl amino, :
non-substituted-phenyl amino, substituted-phenoxy amino, non-substituted-phenyl amino, substituted-phenoxy amino, `
non-substituted phenoxy amino, acetoamino, low alkoxy carbonyl, cyano, substituted-phenyl, non-substituted- ~
phenyl, substituted-di-lower alkyl, and substituted-di- .
lower alkoxy; Rl and R2 are the same or different and represent lower alkyl radicals; R3 represents hydrogen ~

~ 1 - ~ :

:-. - - :

~6~1~5~
or lower alkyl radicals; Y represents oxygen (O) or sulfur (S); and Z represents an alkylene radical of 2 to 4 carbon atoms with or without alkyl substituents necessary to form a ring structure together with -N-C-Y-; and A represents a nitrogen atom substituted by a phenyl radical. -;
The radical A may be the condensation reaction residue of an aromatic nitroso compound.
Useful aromatic nitroso compounds include: -p-dimethyl-aminonitrosobenzene, p-diethylaminonitroso- ;-1~ benzene, p-methyl-nitrosobenzene(p-nitroso-toluene) p-nitro-nitrosobenzene, o-nitro-nitrosobenzene, 3-nitroso-

2-nitrotoluene.
The cell of the present invention can be used, for example, as a display device for a calculator or digital clock or watch in much the same manner as the known liquid crystal display devices. Other uses will be readily apparent to persons skilled in this technology.
This application is closely related to co-pending -Canadian Patent Application Serial No. 235,617 filed on September 17, 1975 of common assignment herewith. -Characteristics of the styryl-like compounds of the present invention are as follows:
(1) Most of the foregoing compounds have absorption in ultraviolet region, and have colorless (transparent) or light yellowish appearance. ;~
(2) When stimulated by light, heat, ions, electricity, pressure or radioactive rays, etc., the compounds are reformed into the belowmentioned open-ring structure of indolenium type.

. .

~ 6 4 85~

( Q ~ C = A

X/ ZYH ~ - (2) 7 ~ :
wherein ~ repr~sents an anion 8uch aa halog~n, -~
ao~d radic~l or alkoxyanion.
~he re~orm~d compound~ fk~ction as color-~orming dyes having absorption in near ultraviolet region, visibla `
regio~ and/or near-in~rared region. -~

(3) ~hs dyes o~ open-ring structure oi indolen~um .:
type again return to indoline ~ype cloged-ring structure by reverse stimulation or el~minat~on o~ the abo~ementlone~
stimula~ionB~
. (4) ~he aboveme~tioned color-change and/or color~
di~appearance-and-reappearance are rever~ble, and these revera~ble changes can be repeated mAny time~, and the - :
reappearing color i~ stable.. Dhe reversibllity depend~ upon strength of the chemical coupling. Thus the stronger the coupling is, the poorer the reversibillty becomes, so that by aelecting su~table component materials, ~arlou~ degree~ o~

the ch~mic 1 coupling la obtainable. :
- (5) The color-rs~toring etructure of tho dye, hence the color obtained, can be ~i2ed b~ selectin~ ths ~olvent, additive~ or-temperat~re. , .-In th6 -~ollowing D variou~ ex~mpleY o~ oompoundB ;~
G~ t~e pre~ant invention a~d their light-absorption wa~ele ~ hs ~;
characteri~tic~ are ~hown: :

~3 - A' - : ,.

.

. . . ~ , ~L~648S~!3 Example 1 3,3-dim6thyl-2-(p~ra-dimethylamino~tyryl) indolino~
~1,2-b~ o~azoli~e N<CH3 ~ ______(3J
maximum abqorption wavelength at clo~ed ring ~tructur~ 296 nm -:
at open ring ~tructur~ 547 nm -' ' ~ample ?
~ ,3-d~methyl-5-methoxy-2-(para-dimethylaminost~r~
indol~no~ b) o~a~olin Q

H~Co;f ~ ~ ~ N<CH~

H2C ------- (4) .
ma~imum ~b30rption wa~elcngth .~ :
at clo~ed ring structure ~ - 297 nm at open ring structure ~ 542 ~m 3,3~dimethyl-5 nitro-2~tpara-dimethylamino~t~r~3 ~`~
indolino~1~2-b) oxazoline N ~ N<CcH3 _____-(S) :. .- . . ~ .. , :

~ 8 5 ~ :

ma~imum absorption wavelength at clo~ed ring ~tructure ~ - 303 nm : at open ring ~tructuro ~ - - 580 nm .

3,3 9 5-trimethyl-2-(para-dimethylaminostyryl)-indolino~1,2-b) oxazoline . ~C ~ N<CH
.- 10 ~ o , (~) , ~C GH2 ' ma~imum ab~orption ~avelength at closed ring structure --- ~ 297 nm at open ring ~truc~urs ~ 547 nm '~
ExamPle, ~ `
3~3-dlmethyl-2-(parà-chlorostyryl)indolino ~1,2-b~
oxazolinc ~;

maximum abæorptio~ wavelength :~
at cloaed r~ng structure . --- 259 nm .
at open ring ~truc~e --- ~ 392 nm , ~ . . . . . - . . . . . ~ . . . . . . .
~. ;. . ~ , . .

~064~358 E~ ~ple 6 3,3-dimethyl-5-chloro-2-(para-chloroatyryl)indolino-~1,2-b) oxa~oline .

~C cH~
ma~imum ab~orption wavelength at closed ring ~tructure -- ~ 255 nm at open ring ~tructure - - ~ 398 nm , ,; , `,, ~ ~`' . ' 3,3-dimethyl-5-chloro-2~para-dimethylami~o~t~r~
indolino~l,2-b) o~azoline ;~ .

~N<CH3 H7C CH2 ~---~
mP~mum ab~orp~ion wa~elength at clo~ed ring ~tructure ~ - - 299 nm a~ open ring Rtructure ___ ~ 557 ~m ~ .
Example 8 3,3-dimethyl-5-lodo-2-~p~ra dimothylamino~tyryl)~
indolino ~,2-b) o~azolin~

'~ <c~

~2.C'~
.;. , _ ,,~ _ ~
6 ~ .

1~648S8 ma::~imum absorption ~a~relength at closcd ring structure --- 298 ~m at open rin~ ~tru~ture ---- 561 nm . , , E"3mP1e 2 3, 3-dimethyl-4, 5-ben~o~2-(para-dlm~thylami~ost~13-inaolino t1 ,2-b~ o:~a~oli~
~ , ' .

~o ~3 , :
H,C
ma~timum ab90rption ~ravel~ngth at ~1088d r~ structur~ - 298 ~
at open r~ ~truoture _- 560 ~m . . -.
'' ' . ',' :

3~-d~meth~1-4,5-b~nzo-2-(para-dimeth~ t~l)-- .
~dol~o( ~2 b)~ tetrahga~oxaz~q `
. -. ' ' , . . .

<CH3 - . -. ~ H2C~ ~CH~
. . . . ..
~ 2) . : ~
.
ma~cimum absorption wa~ele~th . :
-a~ closed ring 8tru¢tur~ --~ 30~. nm -at opa~ rin~ stru~tu~ _ ' ' ' . ' .

.
- ). .. . ' ,~ .

. ~ .. . . ~ . .... . .... ..

^'~
i48 ~1 393-dlmethyl-2-(para-dimsthylaminoclnnamylidene~ingl)-l~dolino~1,2-b~o~azoline H2C - C~2 ______~
ma~imum ab~orption wa~elength at clo3ed ring ~tructure --- ~ 328 nm . ~.
at open ring structure . ~ --- 618 nm 3,3-dimethyl-5-chloro-2-(para-dim~thylaminoci~namyliden@-v~nyl)indolino ~1,2-b30xazoline ~`

H2C--C~ - (14) ma~imum ab~orption wa~elength at clo~ed ring structure - - ~ 338 nm at op~n ring 8truc~ur2 - 63~ nm , ~3~oe 3,3-d~methyl-5-metho~y-2-(para-dimethylaminooinnamyl.ide~e-v~nyl)indolino (1,2-~)oxazolin~

Il~CO~' N<CH~

- ~b--CH2 .

.... . .

106~1~5~

ma~imum absorption ~avelength at closfld ring ~tructure --- ~ 326 nm at open ring ~tructure ~ 594 nm ' ExamP~e~
3,3-dimethyl-2-~para-dlmethylamino-2-aza~tyryl)- . :
indolino~1,2-b)o~azoline ;~

~ cl5 '~

maximum ab~orption wavelength ;~
at clo~ed ring structure ~ 290 nm at open ring Btruotura ~ 587 nm ~-3,3-dimethy1-5-m~tho~y 2-(paradimethylamino-2 aza3tyryl)indol~no~1,2-b)oxazoline ~C0 ~ N ~ N<C~5 H2C ~ (17 - ma~imum absorption waYelength at closed ring structure ~ 271 nm at open ring structure ~ 589 nm ;, ,~, i _ ~ _ ~L~6~6158 xample 1 6 3,3-dimethyl-5-chloro-2-~para-dimethylami~o-2- :
azastyryl~indolino~1,2-b)oxazollne ~3N<~
H2C CH2 -(18) ma~lmum ab~orption wavelength at clo~ed ring structure ~ 301 nm at open ring structure ~ - 600 nm ~-~xamPle 1l 3,3-dimethyl-2-(para-metho~y~tyryl)indolino(1,2-b) ~
tetrahydro~azine). ;~

OC~3 ' ^

~C,CH2 ___ _ - - (lq) ', maximum absorption wavel~ngth at closed ring structur~ ~ 264 ~m ~-at open ring ~tructure -- ~ 423 nm ~xamlple 18 .
3,3-dimethyl-5-chloro-2-(para-dimeth~laminostyryl)-lndolino(1,2-b)-5~-aæoline C~ <CU~

2 ~H2 ~ (20) '': ' . :

-~6~

ma~cimum absorption wa~relength at clo~sd ring ~qtructurs ~ 408tD410 ~n at open ring strusture ~- !;38to540 nm , ExamPle 19 :`-~, 3-dimethyl-2-{2- ( 9-me1;hylca~bazoly~ vinyl}--i:~dolino ¦1 ,2-b~o:cazoline ' ~ '~'' H~C CHz ~ 2~ ) ma~imum absorption wa~elength at clo~ed ring Bt:l'UCtUr~ --- 284t;i~285 nm at ope~ rin~ ~tructure ~ 500tD502 r~m (A) St~lation~: Any o~e o~ the compounds oi` the pre~ent in~ntion change~ color b~ ht-~timulatio~ ;
For e:~;ample, the compound o~ E~ample 1 indisated bg- the chemical formula (~ d~s~ol~ed into n-he~ , the 301utisn ~ ~pplied on a whit~ paper, and then the ~olYent - lq evaporated. When exposed to ultraviolet rays9 the paper becomes pi~k. Tho pink color remalnB ~or a considerabla :
length of tims even a~ter r~moving the ultra~iolet ray80 ~he -reason for this retention of the color is presumably because .:
the compound of the chemical formul~(3) which has b~en ~:
stimulated by th~ ul~ra~iolet ray~ to ~orm open~ring 8tructur~
i8 subsequently ~timulated by anlon~ and proton~ o~ water .
contained in the paper~
Others o~ the abovementioned ~tyryl-like compounds ~:-~lso ~how similar efiact~. For in~tance, the compound oi ~ample 7 indicated by th~ chemical ~ormula(9) change~ ~ts color from tran~parent to red at etimulatio~ by ul~ravlolet rays.

--_ ,~ _ ~ , ~064~1S8 Though ultraviolet rRys al~e ~uitable ~or th~ e~ieGtl~e ~timulation, other ray~, ~or in3tance, vi8ible ray~ can be used i~ a su~icient time 1B given ~or the ~timulationO When a ~la~ sheet ln place o~ the paper 18 employed, the color changes become reversible~ ~ince nelther o~ a~ion n.or proton ex~sta on the glasa.
.. . . . ..... .. , . . , . . . . . , . _ .
~B) ~ g~_h/ ge~ h~ Ar~ o~ the compound~ of the pre~ent invention changes color by heat-stlmulatio~
For example, the compound o~ Example 1 indicated by the chemical ~ormula(3) i~ dis~ol~ed lnto dimeth~l ~ul~oxideO
The transpare~t ~olution i~ ratained ln a thin gap between a pair of gla~ plate~. Whe~ the solution i~ heated gr~dually, the olution turn~ red at above 1~0 C, and turns transparent when the temperature falls.
Such color~changes by heat-~timulation take place at temperature~ around the melting poi~t of the compound~ `
~he color-changlng temperature~ are lowered con,siderabl~
~hen proton~ or anion~ t surrounding tha compound~. -~or another example, when the compound o~ E~ampl~
7 indicated by the chemical ~ormula(5), alone is heated,-the compound ch~n,~es its color ~rom tran~parent to red at about 165 C, while the ~ame compound i~ dissolved in dimeth~lsul~o~ide ~:
containing a small amount of methylalcohol changes to red .
at about 50C.
The hi,gher ths proton concentration arou~d the compound, th~ lower the color changing temperatu~e becomes, For another e~ample~ wha~ the compound o~ Example 2, indicated b~ the chemical ~ormula(4), is dissolved in a non- ~
proton sol~ent and i~ heated, th~n the 801utio~ ChangeB it9 ~ :
color to pink at about 130-C. ~ :~
~or another example, when the compound o~ E~ample 17, indicated by the ~hemical iormula (19), 1~8 dis~olved in non ~ ~: - . , , . : i ~o~

proton solvent and is heated, the solution turns red at about 9 0 C . , , (C) Stimulation b~ electricit~: T~R oompound o~ E~ampl~
indicated by the chemical formula(~ di~sol~ed in dimethyl~uli-oxide. The re~ultant ~olution is then conPin~d in a gla~ cell shown in thc attached ~igure, wherein 1 designated th~ above-mentioned ~olution, numsra~ 2 and 3 de~ignate electricit~co~du¢ti~e ~ilm~ conQtituting a pair o~ electrode, either ona or both oi which are made tran~parent. Numeral~ 4 and 5 designate gla~ plates a~d 6 de~ignate~ a ~pacer o~ a ~peci~i2d thickne~s, for instance 0.005 to 0.1 mm. The spacer i3 made o~ polyethylene terephthalate or poly-fluoroethylene and serves as an insulating side wall encircling :
brims of the glass plates 4,5. When a D.C. or an A.C. voltage is :
impressed across the electrodes 2 and 3, the compound contained in the solution in the cell changes its color. The voltage required to change th~ color i~ 80 low a~, ~or in~tance, 2.0 Yolt~o When th~ -~oltage i~ removed, the color changes ~acl~ Speci~lly, wh~n a D.C. voltage i~ used, and a speci~ied amount o~ reverse bias to ~ :
the preYiou~ly applied D~Co ~oltage i~ applied for a short period ~ -Z at the beglnning oi the reversi~ 9 the color change can be made quick. . . ~ ~ -When the compound OI Example 1, indicated by the chemical ~orDIula(3), i8 con:eined in the cell at the voltage impre~sion~ the ma~imum li~ht ab~orption~ OI the walJelength o~ 552 nm takes place displaying reddish pink color.
When the compound oi E~ample 7, indicated by th3 chemical ~ormula(9), i~ con~ined i~ the cell with the volta~e impres~ion, the mæimum li~ht absorption wavelen~th become~ 557 m showing reddish pink color. :~

. ~ , , .

~:)6~85~
When the compound o~ ~xamp:Le 2, indicated by the chemical formula(4)~ iB confined in the cell wlth the voltage impres~ion, the ma~imum light ab~orption wa~elength becom~
542 ~m ~howing reddi~h pink color. ~:
Eor the abovementioned ~olv~nts 9 those of non-proton nature are ~uitable. ~h~ color changes (and/or reappearance and dissappearance) at voltage impression are presumed to be caused by anions and proton~t and there~or~, mechani~m o~ the color change i8 consider2d to be ~imilar ~o that caused by ions.

. The compound o~ Example 4, indicated by the chemic~l iormula(6), i~ di~persed in gelatin together with, but in separated 3tate irom, acid clay,, and the mixture i~ appli~d on a ~heot o~ paper ~d then dried. The paper 1B white ~hen le~t alone. When some partq o~ the paper are pres~ed, the~
the dye on the pressed part9 reacts with particles o~ the acid ;
clay, and thers~ore, become~ red.
(E) ~ : :
~ The compound o~ E~ample 6, indicated by the ~ormula(8)~
and hydroquinone are dispersed in gelatin each by 10 mol % ~`
concentration. When the resultant mlxture is expo3ed to ràd~a~t ray~
e ectron beam,c~-ra~s or ~ -rays, the mixture become~ blue. Th~ blu0 ~:
color is retained even a~t~r elimination o~ the emission o~ the ~ :
ray~

~.

~, . / Y ' . ~

. - - .. . ... . .
~ ~ '' ' - . ' :: ' ' 6 ~8~ 8 ~ hen the compound of Examplls 18 J indicated by the chemical ~ormula(20)~ i~ dispersed ln tha gelatin in plao~
oi the abo~ementioned compound, th~n th~ mixture becomes red at the exposure to the radiation9 and the red color l~ retained e~en a~ter alimination of the radiation.
When the compound of ~xample 19, indicated by the chemical ~ormulat21)9 i~ u~d in place of the abovementioned compound, the mixture becomes orange~ and thc orange color i~
retained a~ter elimination of ~he radiation.
When the compound o~ Example 6, indl¢ated by the ~ormula (8), and hydro-quinone are dissolved in a non-proton polar solvent each by 10 ~ mol% concentration, then the ml~ture become~ blu~
at the e~po~ure to the radiation, a~d the color changes back aiter elimlnation o~ the radiation.

.
:~

., ' ' ''' , .

, : - ~ - :.

.. . .

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCUSIVE
PROPERTY OR PRIVILGE IS CLAIMED ARE DEFINED AS FOLLOWS:

An apparatus comprising a pair of electrodes, which are arranged with a suitable gap inbetween and at least one of which is transparent, and all insulating spacer, which together with the electrodes constitute a cell containing the solution of a color changing compound, having the belowmentioned chemical formula:

wherein Q represents a benzene ring with or without a second fused benzene ring and/or at least one ring sub-stituent selected from the group consisting of lower alkyl, lower alkoxy, halogen, carboxy, carboalkoxy, nitro, non-substituted-amino, mono-alkyl substituted amino, di-alkyl substituted-amino, substituted-phenyl amino, non-substituted-phenyl amino, substituted-phenoxy amino, non-substituted-phenyl amino, substituted-phenoxy amino, non-substituted phenoxy amino, acetoamino, low alkoxy carbonyl, cyano, substituted-phenyl, non-substituted-phenyl, substituted-di-lower alkyl, and substituted-di-lower alkoxy; R1 and R2 are the same or different and represent lower alkyl radicals; R3 represents hydrogen or lower alkyl radicals; Y represents oxygen (O) or sulfur (S); and Z represents an alkylene radical of 2 to 4 carbon atoms with or without alkyl substituents necessary to form a ring structure together with -N-C-Y-; and A represents a nitrogen atom substituted by a phenyl radical.