Photochromic composition

Abstract

Compounds of the formula I ##STR1## in which X is O, S, SO, SO.sub.2 or NR.sub.13, R.sub.13 is, for example, methyl, and R.sub.1 to R.sub.12, independently of one another, are, for example, H, C.sub.1 -C.sub.12 alkyl, C.sub.1 14 C.sub.12 alkoxy, halogen or --CN. The compounds are photosensitive and photochromic and as suitable are photosensitizers and simultaneously as colour indicators, and as photoswitchable colour filters.

Description

The present invention relates to photochronic acridones, xanthones, thioxanthones, thioxanthone sulfoxides and thioxanthone sulfodioxides which are substituted in the 1-position by substituted or unsubstituted phenoxy, to a process for their preparation, to a photosensitive composition, and to the use of these photochromic compounds as photosensitizers and colour indicators or as photoswitchable colour filters.

It is known that thioxanthones (see U.S. Pat. No. 4,506,083) or thioxanthone sulfoxides or thioxanthone sulfodioxides (see JP Sho 58/120605) are photoinitiators or photosensitizers for irradiation-sensitive polymerizable systems, B. K. Manukian, in Helv. Chim. Acta, vol. 59, Fasc. 7 (1976), pp. 2609 to 2614, described 4-nitroacridones which are 1-substituted by substituted or unsubstituted phenoxy as dyes with good light-fastness properties. DE-A-919 107 described 1-phenoxy-4-methylxanthen-9-one as an active ingredient for pharmaceuticals.

The present invention relates to compounds of the formula I ##STR2## in which X is O, S, SO, SO.sub.2 or NR.sub.13,

R.sub.1 to R.sub.5, independently of one another, are H, C.sub.1 -C.sub.12 -alkyl, C.sub.1 -C.sub.12 alkoxy, C.sub.1 14 C.sub.12 alkylthio, C.sub.1 -C.sub.4 alkyl--SO--, C.sub.1 -C.sub.4 alkyl--SO.sub.2 --, halogen, CF.sub.3, --CN, --NO.sub.2, --OH, --COOR.sub.14, --CON(R.sub.15).sub.2, or --N(R.sub.15).sub.2, or the radical of the formula ##STR3## in which R.sub.16 and R.sub.17, independently of one another, are C.sub.1 -C.sub.6 alkyl, phenyl, C.sub.1 -C.sub.6 alkylphenyl or (C.sub.1 -C.sub.6 alkyl).sub.2 -phenyl, or R.sub.3 and R.sub.4 or R.sub.4 and R.sub.5, in each case together, are --CH.dbd.CH--CH.dbd.CH--, R.sub.6 to R.sub.12, independently of one another, are H, C.sub.1 -C.sub.12 alkyl, C.sub.1 -C.sub.12 alkoxy, C.sub.1 -C.sub.12 alkylthio, C.sub.1 14 C.sub.12 alkyl--SO--, C.sub.1 -C.sub.12 alkyl--SO.sub.2 --, benzyl or C.sub.1 -C.sub.4 alkyl-1-yl which is 1-substituted by a total of one or two --CN and/or --COOR.sub.14, C.sub.6 -C.sub.10 aryl, C.sub.7 -C.sub.14 aralkyl, C.sub.6 -C.sub.10 aryl--CO, C.sub.6 -C.sub.10 aryloxy, C.sub.6 -C.sub.10 arylthio, C.sub.6 -C.sub.10 aryl--SO--, C.sub.6 -C.sub.10 aryl--SO.sub.2, C.sub.7 -C.sub.14 aralkyloxy, C.sub.7 -C.sub.14 aralkylthio, C.sub.7 -C.sub.14 aralkyl--SO--, C.sub.7 -C.sub.14 aralkyl--SO.sub.2 --, C.sub.1 -C.sub.18 acyl--O--, --COOR.sub.14, --CON(R.sub.15).sub.2, C.sub.1 -C.sub.18 aryl--NR.sub.15 --, (R.sub.15).sub.2 N--, halogen, --CF.sub.3 or --CN, or each two adjacent radicals of R.sub.6 to R.sub.12 are the groups --CO--O--CO--or --CO--NR.sub.13 --CO--, the aryl radicals and radicals containing aryl groups being unsubstituted or substituted by halogen, --CN, --CF.sub.3, C.sub.1 -C.sub.6 alkylthio, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkyl, --COOR.sub.14, --CO--N(R.sub.15).sub.2 or C.sub.1 -C.sub.12 acyl--O--, R.sub.13 is H, C.sub.1 -C.sub.12 alkyl or C.sub.1 -C.sub.12 acyl, phenyl or benzyl, which are unsubstituted or substituted by C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkylthio, halogen or --COOR.sub.14, the two R.sub.15 together are C.sub.4 -C.sub.8 alkylene, 3-oxa-1,5-penthylene, 3-thia-1,5-pentylene, 1,3-butandiene-1,4-diyl or 2-aza-1,3-butadiene-1,4-diyl, or the R.sub.15 radicals, independently of one another, are H, C.sub.1 -C.sub.12 alkyl, or phenyl or benzyl which is unsubstituted or substituted by C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkylthio, halogen or --COOR.sub.14, and R.sub.14 is H or the radical of an aromatic or aliphatic alcohol minus the OH group, with the exception of 1-phenoxy-4-methylxanthen-9-one.

Alkyl, alkoxy or alkylthio R.sub.1 to R.sub.5 may be linear or branched and preferably contain from 1 to 6, in particular from 1 to 4, carbon atoms. Examples are methyl, ethyl and the isomers of propyl, butyl, pentyl, hexyl, octyl, nonyl, decyl, undecyl, dodecyl, and the corresponding alkoxy and alkylthio radicals. Preference is given to methyl, ethyl, n- and i-propyl, n-, i- and t-butyl, methoxy, ethoxy, n- and i-propoxy, n-, i- and t-butoxy, methylthio and ethylthio. C.sub.1 -C.sub.4 Alkyl--SO--or C.sub.1 -C.sub.4 alkyl--SO.sub.2 --R.sub.1 to R.sub.5 may be, for example, methyl-, ethyl-, n-propyl- or n-butylsulfinyl or -sulfonyl.

Halogen R.sub.1 to R.sub.5 may be, for example, --F, --Cl, --Br or --I.

--COOR.sub.14 R.sub.1 to R.sub.5 are preferably --COO--C.sub.1 -C.sub.18 alkyl; --N(R.sub.15).sub.2 R.sub.1 to R.sub.5 are preferably --N(C.sub.1 -C.sub.6 alkyl).sub.2 ; and --CON(R.sub.15).sub.2 R.sub.1 to R.sub.5 are preferably --CO--N(C.sub.1 -C.sub.6 alkyl).sub.2 or --CO--NH(C.sub.1 -C.sub.6 alkyl).

R.sub.16 and R.sub.17 are preferably methyl, ethyl, phenyl, methylphenyl or dimethylphenyl.

In a preferred embodiment, R.sub.1 to R.sub.5, independently of one another, are H, C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, halogen, --CF.sub.3, --CN, --NO.sub.2, --COOR.sub.14, --OH, --N(R.sub.15).sub.2 or R.sub.3 and R.sub.4 and R.sub.5, in each case together are --CH.dbd.CH--CH.dbd.CH--, where R.sub.14 is linear or branched C.sub.1 -C.sub.18 alkyl, and each R.sub.15 is C.sub.1 -C.sub.6 alkyl.

In another preferred embodiment, at least 2, in particular at least 3, of the radicals R.sub.1 to R.sub.5 are H.

Alkyl, alkoxy, alkylthio, alkyl--SO--or alkyl--SO.sub.2 --R.sub.6 to R.sub.12 preferably contain from 1 to 6, in particular from 1 to 4, carbon atoms. Examples and further preferences are as given above for R.sub.1 to R.sub.5.

R.sub.6 to R.sub.12 as C.sub.1 -C.sub.4 alk-1-yl or benzyl which is 1-substituted by a total of one or two --CN and/or --COOR.sub.14 may be, for example, cyanomethyl, dicyanomethyl, .alpha.-cyanobenzyl, 1-cyanoeth-1-yl, 1,1-dicyanoeth-1-yl, (metehoxycarbonyl)methyl, (ethoxycarbonyl)methyl, di(methoxycarbonyl)methyl, .alpha.-(methoxycarbonyl)benzyl, 1,1-di(methoxycarbonyl)-eth-1-yl or cyano-(methoxycarbonyl)-methyl.

Aryl R.sub.6 to R.sub.12 are preferably naphthyl and in particular phenyl. R.sub.6 to R.sub.12 as radicals containing aryl groups preferably contain naphthyl and in particular phenyl groups.

Aralkyl R.sub.6 to R.sub.12 are preferably phenyl(C.sub.1 -C.sub.4 alkyl), in particular benzyl or 1-phenyleth-1-yl or -2-yl.

Aryl--CO--R.sub.6 to R.sub.12 are preferably naphthyl--CO--and in particular phenyl--CO--.

Aryloxy R.sub.6 to R.sub.12 are preferably naphythyloxy and in particular phenoxy.

Aryloxy R.sub.6 to R.sub.12 are in particular naphthylthio or phenylthio.

Aryl--SO--or aryl-SO.sub.2 R.sub.6 to R.sub.12 are preferably phenyl--SO-- or phenyl--SO.sub.2 --.

Aralkoxy R.sub.6 to R.sub.12 are preferably phenyl(C.sub.1 -C.sub.4 alkyl)O--, in particular benzyloxy.

Aralkylthio R.sub.6 to R.sub.12 are preferably phenyl(C.sub.1 -C.sub.4 alkyl)S--, in particular benzylthio.

Aralkyl--SO-- R.sub.6 to R.sub.12 are preferably phenyl(C.sub.1 -C.sub.4 alkyl)SO--, in particular benzyl--SO--.

Aralkyl--SO.sub.2 -- R.sub.6 to R.sub.12 are preferably phenyl(C.sub.1 -C.sub.4 alkyl)SO.sub.2 --, in particular benzyl--SO.sub.2 --.

C.sub.1 -C.sub.18 -Acyl--O-- R.sub.6 to R.sub.12 preferably conform to the formula R.sub.19 13 CO--O, in which R.sub.19 is H or C.sub.1 -C.sub.17 alkyl, C.sub.2 -C.sub.17 alkenyl, C.sub.3 -C.sub.8 cycloalkyl, C.sub.6 -C.sub.10 aryl or C.sub.7 -C.sub.14 aralkyl, each of which is unsubstituted or substituted by halogen, preferably --F or --Cl, --OH, C.sub.1 -C.sub.6 alkoxy or C.sub.1 -C.sub.6 alkylthio. R.sub.19 is preferably C.sub.1 -C.sub.12 alkyl, C.sub.2 -C.sub.12 alkenyl, cyclopentyl, cyclohexyl, phenyl or benzyl.

If R.sub.6 to R.sub.12 are the group --COOR.sub.14, R.sub.14 is in particular C.sub.1 -C.sub.18 alkyl.

If R.sub.6 to R.sub.12 are the group --CON(R.sub.15).sub.2 or the group --CONHR.sub.15, R.sub.15 are in particular C.sub.1 -C.sub.6 alkyl.

If R.sub.6 to R.sub.12 are the group C.sub.1 -C.sub.18 acyl-NR.sub.15 --, the group preferably conforms to the formula R.sub.19 -CO--NR.sub.15 --, in which R.sub.19 is as defined for the group R.sub.19 --CO--O--, including the preferences, and R.sub.15 is preferably H or C.sub.1 -C.sub.6 alkyl,

If R.sub.6 to R.sub.12 are the group --N(R.sub.15).sub.2, each R.sub.15 is preferably C.sub.1 -C.sub.6 alkyl, cyclohexyl, phenyl, benzyl, tetramethylene, pentamethylene, 3-oxa-1,5-pentylene or --CH.dbd.CH--CH.dbd.CH--.

Halogen R.sub.6 to R.sub.12 are preferably --F, --Cl or --Br.

If R.sub.6 to R.sub.12 are aryl groups or radicals containing aryl groups, these may be unsubstituted, monosubstituted or polysubstituted, preferably monosubstituted or disubstituted, by halogen, preferably --F, --Cl or --Br, --CN, --OH, --CF.sub.3, C.sub.1 -C.sub.6 alkylthio (for example methylthio or ethylthio), C.sub.1 -C.sub.6 alkoxy (for example methoxy, ethoxy, n- or i-propoxy, n-, i- or t-butoxy), C.sub.1 -C.sub.6 alkyl (for example methyl, ethyl, n- or i-propyl, n-, i- or t-butyl), --COOR.sub.14, in which R.sub.14 is preferably H or C.sub.1 -C.sub.12 alkyl,--CON(R.sub.15).sub.2, in which R.sub.15 is preferably H or C.sub.1 -C.sub.6 alkyl, or C.sub.1 -C.sub.12 acyl--O--, preferably C.sub.1 -C.sub.11 alkyl--CO--O--.

Alkyl R.sub.13 preferably contains from 1 to 6, in particular from 1 to 4, carbon atoms and is, for example, methyl or ethyl. Acyl R.sub.13 is preferably R.sub.19 --CO--, in which R.sub.19 is as defined above and is in particular C.sub.1 -C.sub.8 alkyl, cyclohexyl, phenyl or benzyl.

An alcohol radical R.sub.14 preferably contains from 1 to 30, in particular from 1 to 20, especially from 1 to 10, carbon atoms. An aromatic alcohol radical R.sub.14 may be C.sub.6 -C.sub.10 aryl, in particular phenyl or phenyl(C.sub.1 -C.sub.4 alkyl), in particular benzyl or 1-phenyleth-2-yl, which may be substituted by 1 or 2 C.sub.1 -C.sub.18 alkyl, in particular C.sub.1 -C.sub.12 alkyl groups.

An aliphatic radical R.sub.14 may be an open-chain or cyclic radical, e.g. C.sub.1 -C.sub.20 alkyl, in particular C.sub.1 -C.sub.18 alkyl, especially C.sub.1 -C.sub.12 alkyl; C.sub.3 -C.sub.8 cycloalkyl or C.sub.3 -C.sub.8 cycloalkylmethyl, in particular cyclopentyl, cyclohexyl or cyclohexylmethyl.

R.sub.14 may alternatively be a polyoxaalkylene radical of the formula --C.sub.n H.sub.2n --O R.sub.18 in which n is an integer from 2 to 6, in particular from 2 to 4, especially 2 or 3, and m is a number from 1 to 20, in particular 1 to 12, especially 1 to 6, and R.sub.18 is H, C.sub.1 -C.sub.18 alkyl, in particular C.sub.1 -C.sub.12 alkyl, especially C.sub.1 -C.sub.6 alkyl, C.sub.3 -C.sub.8 cycloalkyl, in particular C.sub.5 - or C.sub.6 cycloalkyl or cycloalkylmethyl; or phenyl or benzyl, which may be substituted by 1 or 2 alkyl groups having from 1 to 12, in particular from 1 to 6, carbon atoms.

Alkyl R.sub.15 preferably contains from 1 to 5, in particular from 1 to 4, carbon atoms and is in particular methyl or ethyl. Substituted phenyl or benzyl R.sub.15 preferably contains 1 or 2 substituents. Halogen and --COOR.sub.14 as substituents are preferably --F, --Cl, --Br, --COOH and --COO(C.sub.1 -C.sub.12 alkyl). The two R.sub.15 radicals together, as alkylene, are preferably tetramethylene or pentamethylene.

In a preferred embodiment at least 2, in particular at least 3 and especially at least 4, of the radicals R.sub.6 R.sub.12 are H.

A preferred subgroup of compounds of the formula I comprises those in which R.sub.6 to R.sub.12, independently of one another, are H, C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkylthio, C.sub.1 -C.sub.6 alkyl--SO--, C.sub.1 -C.sub.6 alkyl-SO.sub.2, C.sub.1 - or C.sub.2 alkyl which is 1-substituted by a total of one or 2-CN and/or COOR.sub.14, phenyl, phenyl-C.sub.1 -C.sub.4 alkyl, phenyl--CO--, phenyloxy, phenylthio, phenyl--SO--, phenyl--SO.sub.2 --, benzyloxy, benzylthio, benzyl--SO--, benzyl--SO.sub.2 --, C.sub.1 -C.sub.8 acyl--NR.sub.15 --, --COOR.sub.14, --CON(R.sub.15).sub.2, (R.sub.15).sub.2 N--, --F, --Cl, --Br, --CF.sub.3 or --CN or each two adjacent R.sub.6 to R.sub.12 radicals together are --CO--O--CO-- or --CO--NR.sub.13 --CO--, R.sub.13 is C.sub.1 -C.sub.6 alkyl, or phenyl or benzyl which are unsubstituted or substituted by C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, F, Cl, Br or --COOR.sub.14, R.sub.14 is H, linear or branched C.sub.1 -C.sub.18 alkyl, phenyl, benzyl or --C.sub.n H.sub.2n --O R.sub.18, where n is an integer from 2 to 6, and m is a number from 1 to 20, and R.sub.18 is H, C.sub.1 -C.sub.18 alkyl, cyclohexyl, phenyl or benzyl, and

R.sub.15 is C.sub.1 -C.sub.6 alkyl, or phenyl or benzyl which is unsubstituted or substituted by C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, --F, --Cl, --Br or --COOR.sub.14, or the two R.sub.15 radicals together are 1,4-butylene, 1,5-pentylene, 3-oxa-1,5-pentylene or 1,3-butadiene-1,4-diyl.

Preferred groups of compounds are also those in which, in the formula I, R.sub.6 is H, --Cl, --Br or methyl, or in which, in the formula I, R.sub.9 is H or --Cl, or in which, in the formula I, R.sub.11 is H or --Cl, or in which, in the formula I, R.sub.10 and/or R.sub.12 is --Cl, --Br, unsubstituted or substituted phenoxy or --COO--(C.sub.1 -C.sub.12 alkyl), or in which, in the formula I, R.sub.7 and/or R.sub.8 is H, --F, --Cl, --CF.sub.3, --Br, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, phenyl--CO--, .alpha.-cyanobenzyl, C.sub.1 -C.sub.8 acyl-NR.sub.15 -, pyrryl, --COO--(C.sub.1 -C.sub.12 alkyl), or phenoxy, phenylthio or phenylsulfonyl, which are unsubstituted or substituted by --F, --Cl, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, --COOH or --COO--(C.sub.1 -C.sub.12 alkyl), or R.sub.7 and R.sub.8 together are ##STR4## and R.sub.13 is H or C.sub.1 -C.sub.6 alkyl, or in which, in the formula I, R.sub.13 is C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.8 acyl, or phenyl or benzyl which are unsubstituted or substituted by F or --COOR.sub.14, and R.sub.14 is H or C.sub.1 -C.sub.12 alkyl, or in which, in the formula, I, R.sub.14 is H, C.sub.1 -C.sub.18 alkyl, --C.sub.n H.sub.2 n --O H, phenyl, C.sub.1 -C.sub.6 alkylphenyl, benzyl, C.sub.1 -C.sub.6 alkylbenzyl or cyclohexyl, n is an integer from 1 to 6, and m is a number from 1 to 20, or in which, in the formula I, R.sub.15 is H, C.sub.1 -C.sub.6 alkyl, phenyl, benzyl, or the two R.sub.15 radicals together are tetramethylene, pentamethylene, 3-oxa-1,5-pentylene or 1,3-butadiene-1,4-diyl.

Particularly preferred compounds of the formula I are those in which R.sub.1 to R.sub.5 are H or R.sub.1, R.sub.2, R.sub.4 and R.sub.5 are H and R.sub.3 is --CO.sub.2 C.sub.2 H.sub.5, R.sub.6 and R.sub.8 are Cl, and R.sub.7 and R.sub.9 -R.sub.12 are H, and X is NCH.sub.3 or N--n--C.sub.3 H.sub.7.

The compounds according to the invention can be obtained in a manner known per se by nucleophilic substitution of 1-nitro- or 1-haloxanthones, -thioxanthones, -thioxanthone sulfoxides, -thioxanthone sulfodioxdes or -acridones by phenol salts. The invention furthermore relates to a process for the preparation of compounds of the formula I which comprises reacting a compound of the formula II ##STR5## in which X and R.sub.6 to R.sub.12 are as defined in claim 1, and Y is --NO.sub.2 or halogen, with a compound of the formula III ##STR6## in which R.sub.1 to R.sub.5 are as defined in claim 1, and M.sym. is an alkali metal cation, or a quaternary ammonium or phosphonium cation, at elevated temperature in the presence of a dipolar aprotic or protic solvent.

The process according to the invention is preferably carried out at temperatures of from 50.degree. to 200.degree. C., in particular from 50.degree. to 150.degree. C. The salts of the formula III can be employed as such or produced in situ in the reaction mixture by reacting an appropriate phenol with an alkali metal, ammonium or phosphonium base. The salts of the formula III can be employed in equimolar amounts or in excess, e.g. an excess of up to 40 mol %.

Examples of suitable solvents are N-substituted carboxamides and lactams (for example dimethylformamide or N-methylpyrrolidone), sulfoxides and sulfones (for example dimethyl sulfoxide or tetramethylene sulfone) or ethers (for example, di-n-propyl ether, di-n-butyl ether, tetrahydrofuran or dioxane).

The compounds of the formula I are isolated and purified by conventional methods, for example by crystallization and recrystallization, or by chromatography.

The compounds of the formula III are known or can be obtained in a known manner by reacting appropriate phenols with alkali metal, ammonium or phosphonium bases. Particularly suitable alkali metal cations are Li.sym., Na.sym. and K.sym.; and examples of particularly suitable quaternary onium cations are (C.sub.1 -C.sub.6 alkyl).sub.4 N.sym., (C.sub.1 -C.sub.6 alkyl)P.sym. or tetraphenylphosphonium.

Compounds of the formula I containing functional groups, for example --COOH or --NH.sub.2, can be derivatized in a known manner to give esters or amides.

Some of the compounds of the formula II in which Y, as halogen, is preferably --F, --Cl or --Br are known or can be prepared by processes known per se by intraocular Friedel-Crafts acylation (thioanthones, see, for example U.S. Pat. No. 4,385,182 or F. Mayer, Chem. Ber. 43, pp. 584 ff (1910); xanthones, see, for example, F. Ullmann et al., Chem. Ber. 38, pp. 2120 ff (1905); acridones, see for example, C. W. Renocastle et al., Synthesis 1985, pp. 21 ff). Thioanthone sulfoxides and sulfodioxides can also be obtained by oxidation of the thioxanthones.

Compounds of the formula I are heat resistant, colourless to slightly yellow and predominantly crystalline and are soluble in organic solvents. They are highly effective photoinitiators and photosensitizers for photopolymerizable or photodimerizable systems which contain ethylenically unsaturated double bonds.

When the compounds are irradiated, alone or in a substrate, with light having a wavelength of from about 300 to 450 nm, a pronounced colour change to blue/violet is suprisingly found. This colour change is irrevesible.

The compounds of the formula I can therefore be used as photoinitators and in particular as photosensitizers in photopolymerizable systems, with a simultaneous action as colour indicators. It is thus possible to mark exposed products (for example protective coatings, printing plates, offset printing plates, printed circuits, solder stop masks) and to differentiate them from unexposed products, and furthermore to separate out products which have been exposed incorrectly, during product monitoring or after development.

The substantial advantage when used as colour indicators is the increase in the sensitizer action. Additives usually employed as colour-change systems cause a reduction in photosensitivity.

The compounds of the formula I can also be used as such, in solution or incorporated into polymers as colour photoindicators or as photoswitching elements.

The invention furthermore relates to a radiation-sensitive composition containing

a) a radiation-sensitive organic material, and b) at least one compound of the formula I, including 1-phenoxy-4-methylxanthen-9-one.

The compounds of the formula I can be present in an amount of from 0.001 to 20% by weight, in particular from 0.001 to 10% by weight, especially from 0.01 to 5% by weight, based on component a).

Radiation-sensitive and thus also photostructurable materials are known. They may be positive or negative systems. Such materials are described, for example, by G. E. Green et al., in J. Macro. Sci. Revs. Macr. Chem., C21(2), 187-273 (1981-82) and by G. A. Delzenne in Adv. Photochem., 11, pp. 1-103 (1979).

The radiation-sensitive organic material is preferably a1) a nonvolatile monomeric, oligomeric or polymeric substance containing photopolymerizable or photodimerizable, ethylenically unsaturated groups, a2) a cationically curable system or a3) photocrosslinkable polyimides.

Examples of photopolymerizable substances are acrylates and in particular methacrylates of polyols, e.g. ethylene glycol, propanediol, butanediol, hexanediol, di(hydroxymethyl)cyclohexane, 2,2-bis(4-hydroxyethoxyphenyl)propane, polyoxyalkylenediols, for example di-, tri- or tetraethylene glycol, di- or tri-1,2-propylene blycol, trimethylolmethane, -ethane or -propane and pentaerythritol, which can be used alone, in mixtures and blended with binders. Products of the addition of acrylic acid and in particular methacrylic acid onto bisglycidyloxy compounds, for example 2,2-bis(4-glycidyloxyphenyl)propane, are also suitable, Methylenebisacrylamide is furthermore suitable.

Examples or photodimerizable substances are homopolymers and copolymers which contain cinnamic acid groups or substituted maleinimidyl compounds in side groups or chalcone groups in the polymer chain.

Preferred compositions of this type are those in which component a1) is a homopolymer or copolymer of acrylates, methacrylates or maleates whose ester groups contain a radical of the formula ##STR7## in which A is unsubstituted or hydroxyl-substituted, linear or branched C.sub.2 -C.sub.12 alkylene, cyclohexylene or phenylene, and R.sub.20 and R.sub.21, independently of one another, are Cl, Br, phenyl or C.sub.1 -C.sub.4 alkyl, or R.sub.20 and R.sub.21 together are trimethylene, tetramethylene or ##STR8## Polymers of this type are described, for example, in U.S. Pat. No. 4,193,927.

The photopolymerizable or photodimerizable substances may contain further additives which are customary for processing or application and in addition other photoinitiators or photosensitizers.

The cationically curable systems are preferably epoxide compounds containing at least two epoxide groups in the molecule and mixed with a photoinitiator. Examples of suitable photoinitiators are metallocenes, metallocene carbonyls and onium salts, which are described, for example, in the abovementioned publications. The curable systems may contain additives which are customary for processing and application.

Photosensitive polyimides are described, for example, in DE-A-1 962 588, EP-A-0 132 221, EP-A-0 134 752, EP-A-0 162 017, EP-A-0 181 837 and EP-A-0 182 745.

The composition according to the invention is applied as a coating to substrates by known methods, and either a protective coating is produced by irradiation over the entire area or a relief image is produced by irradiation under a photomask with subsequent development.

The invention furthermore relates to a composition containing

a) a colourless, organic solvent, a polymer or an organic glass or a composite glass, and b) a compound of the formula I, including 1-phenoxy-4-methylxanthen-9-one. Component b) is preferably present in an amount of from 0.001 to 20% by weight, in particular from 0.001 to 10% by weight, especially from 0.01 to 5% by weight based on component a). Organic solutions can be used to coat other substances, e.g. inorganic glasses, which can then be used as photoswitchable substrates. The compounds of the formula I can also be sublimed onto substrates. The coated substrates can be provided with a protective coating of, for example, transparent polymers. Examples of suitable solvents are hydrocarbons, halogenated hydrocarbons, ketones, carboxylic acid esters and lactones, N-alkylated acid amides and lactams, alkanols and ethers.

Examples of suitable polymers are thermosets, thermoplastics and structurally crosslinked polymers. The polymers are preferably transparent. Such polymers and organic glasses are known to those skilled in the art. The compounds according to the invention are incorporated by conventional methods, e.g. by dissolution and removal of the solvent, calendering or extrusion. The compounds according to the invention can also be incorporated into the substrates before, during or after preparation.

The invention furthermore relates to a process for the production of coloured materials under the action of light, which comprises incorporating a compound of the formula I, including 1-phenoxy-4-methylxanthen-9-one, into the material and then irradiating the material with light.

The invention furthermore relates to the use of compounds of the formula I, including 1-phenoxy-4-methylxanthen-9-one, as photosensitizers and colour indicators or photoswitching elements under the action of light.

The examples below illustrate the invention in greer detail.

A) Preparation examples

Examples A1-A76

16 mmol of 1-haloxanthone, -thioxanthone or -acridone, 24 mmol of phenol, 40 mmol of potassium carbonate and 45 ml of solvent are warmed with stirring. the reaction mixture is poured into 200 ml of ice, and the precipitate is filtered off and dissolved in toluene/tetrahydrofuran (1:1). The solution is washed successively with 5% strength NaOH, water and saturated aqueous sodium chloride solution, and dried using sodium sulfate. The solvent is removed by distillation, and the residue is recrystallized from toluene/isopropanol (1:1).

Further details are given in Tables 1a and 1b. The data relate to the formula ##STR9##

TABLE 1a Melting No. A X R R.sub.6 R.sub.7 R.sub.8 R.sub.9 R.sub.10 R.sub.11 R.sub.12 point (.degree.C.) 1 O Ph H OPh H H H H Cl 168-176 2 O Ph H OPh H H H H OPh 181-183 3 O Ph H OPh H Cl OPh Cl CO.sub.2 C.sub.2 H.sub.5 195-197 4 O Ph H Cl H H H H Cl 152-154 5 O Ph H Cl H Cl Cl Cl CO.sub.2 C.sub.2 H.sub.5 229-231 6 N-3,5-F.sub.2 Ph Ph H F H H H H H 7 NC.sub.2 H.sub.5 Ph H Cl H H H H H 189-191 8 NCH.sub.2 Ph Ph H F H H H H H 223-225 9 NCH.sub.3 Ph H OPh H H H H H 100-105 10 NCH.sub.3 Ph H H H H H H CF.sub.3 142-145 11 N-2-COOHPh Ph H Cl H H H H H <260 12 NC.sub.2 H.sub.5 3-BrPh H Cl H H H H H 183-187 13 NC.sub.2 H.sub.5 4-ClPh H Cl H H H H H 147-148 14 NC.sub.2 H.sub.5 Ph H PhO H H H H H 164-65 15 NC.sub.2 H.sub.5 3-BrPh H 3-BrPhO H H H H H 126-129 16 NCH.sub.3 Ph H H Cl H H H H 129-130 17 NC.sub.2 H.sub.5 3,5-(CH.sub.3 O).sub.2 Ph H 3,5-(CH.sub.3 O).sub.2 PhO H H H H H 152-154 18 NC.sub.2 H.sub.5 3,5-(CH.sub.3 O).sub.2 Ph H Cl H H H H H 180-183 19 NC.sub.2 H.sub.5 4-ClPh H 4-ClPhO H H H H H 148-149 20 NC.sub.2 H.sub.5 4-(oct-2-yl-O.sub.2 C)Ph H Cl H H H H H Oil 21 NC.sub.2 H.sub.5 4-(oct-2-yl-O.sub.2 C)Ph H 4-(oct-2-yl-O.sub.2 C)PhO H H H H H Oil 22 NC.sub.2 H.sub.5 4-(C.sub.2 H.sub.5 O.sub.2 C)Ph H Cl H H H H H 138-140 23 N-i-propyl Ph H Cl H H H H H 143-145 24 Ph H Cl H H H H H 144-147 25 ##STR10## Ph H OPh H H H H H 60-70 26 ##STR11## Ph H Cl H H H H H 102-104 27 ##STR12## Ph H OPh H H H H H 102-105 28 NC.sub.2 H.sub.5 Ph H Cl H H H H H 128-130 29 NCH.sub.3 Ph Cl H Cl H H H H 173-174 30 NC.sub.3 H.sub.7 Ph Cl H Cl H H H H 116- 118 31 S Ph Cl Cl Cl H H H H 190-192 32 S Ph Cl PhO Cl H H H H 203-204 33 S Ph Br H F H H H H 199-202 34 S Ph H H CH.sub.3 O H H H H 191-193 35 S Ph Cl H Cl H H H H 183-185 36 S 4-NO.sub.2Ph Cl H Cl H H H H 228-230 37 S 4-FPh Cl H Cl H H H H 149-150 38 S 4-BrPh Cl H Cl H H H H 217-219 39 S 4-ClPh Cl H Cl H H H H 192-195 40 S 4-IPh Cl H Cl H H H H 236-238 41 S 4-CH.sub.3Ph Cl H Cl H H H H 175-177 42 S 4-CH.sub.3 OPh Cl H Cl H H H H 153-155 43 S (C.sub.2 H.sub.5).sub.2 NPh Cl H Cl H H H H 134-135 44 S 3-ClPh Cl H Cl H H H H 150-152 45 S 3-CH.sub.3 OPh Cl H Cl H H H H 169-171 46 S 3,5-(CH.sub.3 O).sub.2Ph Cl H Cl H H H H 192-194 47 S 2,4-Cl.sub.2Ph Cl H Cl H H H H 235-237 48 S 3-BrPh Cl H Cl H H H H 172-174 49 S 3,4-Cl.sub.2Ph Cl H Cl H H H H 187-188 50 S Ph Cl H Cl H H CO.sub.2 C.sub.2 H.sub.5 H 178-183 51 S 4-CNPh Cl H Cl H H H H 248-251 52 S 4-(C.sub.2 H.sub.5 O.sub.2 C)Ph Cl H Cl H H H H 172-174 53 S 4-t-octyl-Ph Cl H Cl H H H H 137-139 54 S 4-(n-C.sub.12 H.sub.25 O.sub.2 C)Ph Cl H Cl H H H H 109-112 55 S Ph Cl H Cl H C.sub.2 H.sub.5 O.sub.2 C H H 170-173 56 S Ph CH.sub.3 H CH.sub.3 H H H C.sub.2 H.sub. 5 O.sub.2 C 153-155 57 S 4-(n-C.sub.12 H.sub.25 O.sub.2 C)Ph Cl H Cl H C.sub.2 H.sub.5 O.sub.2 C H H 129-133 58 S 3-(C.sub.2 H.sub.5 O.sub.2 C)Ph Cl H Cl H H H H 163-165 59 S 3-CF.sub.3Ph Cl H Cl H H H H 167-169 60 S Ph Cl H Cl H H H C.sub.2 H.sub.5 O.sub.2 C 168-170 61 S Ph Cl H Cl H H H ##STR13## 127-129 62 S 4-(n-C.sub.12 H.sub.25 O.sub.2 C)Ph Cl H Cl H H H ##STR14## Oil 63 S 1-naphthyl Cl H Cl H H H H 247-249 64 S 2-naphthyl Cl H Cl H H H H 197-200 65 S 3-OH-4-R'-Ph Cl H Cl H H H H 235-238 66 S Ph H Cl H H H H H 114-116 67 S Ph H PhO H H H H H 151-153 68 S 2,4-Cl.sub.2Ph H Cl H H H H H 205-208 69 S 3,5-Cl.sub.2Ph H Cl H H H H H 195-197 70 S 3,5-Cl.su b.2Ph H 3,5-Cl.sub.2Ph H H H H H 202-204 71 S 3,5-Cl.sub.2Ph Cl H Cl H H H H 214-218 72 S Ph H Cl Cl H H H H 162-165 73 S 3-CH.sub.3 OPh H Cl H H H H H 102-104 74 S 3-CH.sub.3 OPh Cl Cl Cl H H H H 172-174 75 S 3-CH.sub.3 OPh Cl 3-CH.sub.3 OPh Cl H H H H -- 76 S Ph Br H Br H H H H 174-176 TABLE 1b______________________________________ Reaction ReactionNo. temperature time YieldA 1-Halogen Solvent (.degree.C.) (h) (%)______________________________________ 1 Cl DMSO 120 19 4 2 Cl DMSO 120 19 7 3 Cl DMSO 120 18 53 4 Cl Bu.sub.2 O 120 23 52 5 Cl Bu.sub.2 O 130 21 44 6 F Dioxane 100 3 33 7 Cl Bu.sub.2 O 150 72 84 8 F Dioxane 100 4 76 9 Cl DMSO 120 2 7810 F DMSO 100 36 4511 Cl DMSO 130 18 5812 Cl Bu.sub.2 O 140 24 7213 Cl Bu.sub.2 O 140 16 6614 Cl DMSO 140 23 8015 Cl DMSO 140 23 7516 Cl DMSO 130 24 7117 Cl DMSO 140 18 5218 Cl Bu.sub.2 O 140 64 2419 Cl DMSO 140 19 7220 Cl Bu.sub.2 O 140 40 9521 Cl DMSO 140 61 5422 Cl Bu.sub.2 O 140 42 3123 Cl DMSO 140 45 6424 Cl Bu.sub.2 O 140 5 days 2125 Cl Bu.sub.2 O 140 5 days 1526 Cl Bu.sub.2 O 140 68 6127 Cl Bu.sub.2 O 140 68 828 Cl Bu.sub.2 O 140 69 5329 Cl NMP 100 18 9330 Cl DMSO 110 3 8331 Cl Dioxane 120 24 4432 Cl Dioxane 120 24 1333 F Bu.sub.2 O 130 17 7534 F DMSO 130 9 3635 Cl DMSO 90 23 5836 Cl DMSO 120 23 1737 Cl DMSO 90 23 5838 Cl DMSO 80 28 5539 Cl DMSO 80 28 5140 Cl DMSO 80 17 4841 Cl DMSO 80 17 5842 Cl DMSO 80 19 6543 Cl DMSO 100 20 3444 Cl DMSO 80 21 6145 Cl DMSO 100 6 5546 Cl DMSO 100 18 6447 Cl DMSO 120 24 4748 Cl DMSO 80 18 6049 Cl DMSO 100 18 5650 Cl DMSO 80 3 7051 Cl DMSO 100 19 5852 Cl DMSO 100 15 6153 Cl DMSO 80 16 5354 Cl DMSO 100 18 4955 Cl DMSO 80 18 5556 Br DMSO 140 32 357 Cl DMSO 90 22 5758 Cl DMSO 80 22 5659 Cl DMSO 90 6 6160 Cl DMSO 80 16 6761 Cl DMSO 80 6 6562 Cl DMSO 100 6 8863 Cl DMSO 100 22 5264 Cl DMSO 100 22 5865 Cl DMSO 100 18 7366 Cl Dioxane 100 47 6367 Cl DMSO 120 20 9768 Cl Dioxane 100 72 2769 Cl Dioxane 100 72 8070 Cl DMSO 120 18 7071 Cl DMSO 100 3 4672 Cl Bu.sub.2 O 130 96 4273 Cl Dioxane 100 72 5274 Cl Bu.sub.2 O 140 7 8075 Cl -- -- -- .sup. 4.sup.1)76 Br Bu.sub.2 O 140 20 69______________________________________ Abbreviations: DMSO: Dimethyl sulfoxide Bu.sub.2 O: Di(n-butyl) ether NMP: Nmethylpyrrolidone Ph: Phenyl ##STR15## .sup.1) By product from Example A74

Example A77-A82

3-Methoxy-1-phenoxythioxanthone

340 mg (1 mmol) 3-chloro-1-phenoxythioxanthone, 3 ml (75 mmol) of methanol and 420 mg (3 mmol) of potassium carbonate are heated at 110.degree. C. for 24 hours in 5 ml of dimethyl sulfoxide. The reaction mixture is poured into water and neutralized using dilute hydrochloric acid, and the product is extracted with toluene/tetrahydrofuran. The organic phase is washed with saturated aqueous sodium bicarbonate solution, dried using sodium sulfate and evaporated. The residue is purified by chromatography (silica gel, hexane/ethyl acetate 10:1) and subsequently recrystallized from toluene. Yield: 113 mg (34%), melting point 154.degree.-156.degree. C.

The following compounds (Table 2) are prepared analogously using sodium phenylsulfinate, thiophenol, sodium methylmeracptide or thiosalicylic acid:

__________________________________________________________________________Example Yield MeltingNo. A X R R.sub.6 R.sub.7 R.sub.8 R.sub.9 R.sub.10 R.sub.11 R.sub.12 (%) point (.degree.C.)__________________________________________________________________________78 S Ph H SO.sub.2 Ph H H H H H 80 201-20479 S Ph H SPh H H H H H 78 161-163.580 S Ph H SCH.sub.3 H H H H H 5 173-17681 S Ph H ##STR16## Cl H H H H 46 247-25082 S Ph H ##STR17## H H H H H 50 150-152__________________________________________________________________________

Example A83

N-Methyl-phenoxy-4-pyrrolylacridone

1.3 g (4 mmol) of 4-amino-N-methyl-1-phenoxyacridone and 0.8 g (6 mmol) of 2,5-dimethoxytetrahydrofuran are heated at 130.degree. C. for 30 minutes in 10 ml of glacial acetic acid. The reaction mixture is then poured into 100 ml of water, and the product is extracted with toluene/tetrahydrofuran. The organic phase is washed successively with saturated aqueous sodium bicarbonate solution, water and saturated aqueous sodium choride solution, dried using sodium sulfate and evaporated. Purification by column chromatography (Silica gel, ether/hexane 1:1) and subsequent recrystallization from toluene/isopropanol gives the desired product. Further details are given in Table 3.

Examples A84-A86

The compounds of Examples A84-A86 are prepared analogously to Example A83, with 2,5-dimethoxytetrahydrofuran being replaced in Example A85 by 2,3-dimethylsuccinic anhydride and in Example A86 by dimethylmaleic anhydride. Further details are given in Table 3.

TABLE 3__________________________________________________________________________Example Yield MeltingNo. A X R R.sub.6 R.sub.7 R.sub.8 R.sub.9 R.sub.10 R.sub.11 R.sub.12 (%) point__________________________________________________________________________ (.degree.C.)83 NCH.sub.3 Ph H H ##STR18## H H H H 87 177-18084 S Ph H H ##STR19## H H H H 64 164-16685 NCH.sub.3 Ph H H ##STR20## H H H H 85 221-22386 NCH.sub.3 Ph H H ##STR21## H H H H 79 248-249__________________________________________________________________________

Example A87

4-Acetylamino-N-methyl-1-phenoxyacridone

1.3 ml (16 mmol) of pyridine and 0.28 (4 mmol) of acetyl chloride are added to a solution of 0.7 g (2 mmol) of 4-amino-N-methyl-1-phenoxyacridone in 20 ml of chloroform, and the mixture is stirred at room temperature for 6 hours. The solution is washed with hydrochloric acid (18%), water and saturated aqueous sodium chloride solution, dried using sodium sulphate and evaporated. The residue is washed with diethyl ether nad filtered off. Yield: 0.6 g (83%) melting point: 252.degree.-254.degree. C.

Example A88 and A89

The following are obtained in an analogous manner to that in Example A87

A88: 4-(2-Ethylhexanoylamino)-N-methyl-1-phenoxyacridone, melting point 154.degree.-156.degree. C., yield 70%.

A89: 4-(3-Chloro-2,2-dimethylpropionylamino)-N-methyl-1-phenoxyacridone, melting point: 218.degree.-218.degree. C., yield: 80%.

Example A90

2,4-Dichloro-1-phenoxythioxanthone sulfoxide

A solution of 3 g (8 mmol) of 2,4-dichloro-1-phenoxythioxanthone and 0.9 g (8 mmol) of H.sub.2 O.sub.2 (30%) in 100 ml of glacial acetic acid is refluxed for 1 hour. The mixture is subsequently poured into 250 ml of water and extracted with 150 ml of toluene. The organic phase is washed with water, aqueous sodium bicarbonate solution (10%) and saturated aqueous sodium chloride solution, dried using sodium sulfate and evaporated. The residue is recrystallized from toluene/isopropanol. Yield 2.1 g (67%) melting point: 207.degree.-209.degree. C.

Example A91

2,4-Dichloro-1-phenoxythioxanthone sulfodioxide

If the reaction is carried out using 2.7 g of H.sub.2 O.sub.2 (24 mmol) (30%) and the product is purified by column chromatography (silica gel, CH.sub.2 Cl.sub.2), 3.26 g (74%) of the sulfone are obtained; melting point: 197.degree.-198.degree. C.

Example A92

1-(3',5'-Dichlorophenoxy)-3-(.alpha.-cyanobenzyl)thioxanthone

2 g (4.9 mmol) of 1-(3',5'-dichlorophenoxy)-3-chlorothioxanthone, 0.86 g of benzyl cyanide, 2.03 g of potassium carbonate and 20 ml of DMSO are stirred at 80.degree. C. for 6 hours. The mixture is discharged into 2N HCl/tetrahydronfuran/toluene, and the organic phase is separated off, dired over sodium sulfate and evaporated. Chromatography on silica gel using methylene chloride gives 0.72 g (30%) of product, melting point 145.degree.-155.degree. C.

Example A93

1-(3',5'-Dichlorophenoxy)-3-benzoylthioxanthone

0.3 g (0.61 mmol) of the compound of Example A92 is stirred at 60.degree. C. with 130 mg (0.92 mmol) of potassium carbonate and 5 ml of DMSO, Air is passed into the mixture for 6 hours at 60.degree. C. The mixture is worked up as in Example A92, and the crude product is recrystallized from methylene chloride/pentane. Yield 0.20 g (69%), melting point 160.degree.-163.degree. C.

Example A94

1-Phenoxythioxanthone 3,4-N-butylimide

3.0 g(7.8 mmol) of 1-nitrothioxanthone 3,4-N-butylimide, 0.89 g (9.4 mmol) of phenol, 2.16 g (15.7 mmol) of potassium carbonate and 30 ml of DMSO are stirred at 25.degree. C. for 2 hours. The mixture is discharged into 2N HCl/methylene chloride. The organic phase is separated off, dired over sodium sulfate and evaporated. Recrystallization from methylene chloride/pentane gives 2.88 g (86%) of product of melting point 198.degree.-199.degree. C.

Example A95 and A96

The following compounds are obtained analogously to Example A94, using the appropriate phenols:

A95: 1-(3,5-Dichlorophenoxy)thioxanthone 3,4-N-butylimide, melting point 207.degree.-213.degree. C. yield 81%.

A96: 1-(2-Methoxy-4-formylphenoxyl)thixanthone 3,4-N-butylimide, melting point 260.degree.-263.degree. C., yield 78%.

Example A97

2,4-Dichloro-1-(3-hydroxyphenyl)-N-methylacridone

8 g (25.6 mmol) of N-methyl-1,2,4-trichloroacridone, 8.46 g (76.8 mmol) of resorcinol, 14.15 g (102.4 mmol) of potassium carbonate and 80 ml of NMP are stirred at 60.degree. C. for 30 hours. The mixture is discharged into water/tetrahydrofuran/toluene. The organic phase is washed with water, dried over sodium sulfate, filtered through silica gel and evaporated. The residue is chromatographed on silica gel using methylene chloride. The fractions containing the product are evaporated, and the residue is recrystallized from 0-dichlorobbenzene: Yield 5.45 g (55%), melting point 220.degree.-222.degree. C.

B) USE EXAMPLES

Example B1

1.8 g of the compound from Example A6 are dissolved in 60 mg of methyl methacrylate, and 3.6 mg of azobisisobutyronitrile are added. Using a syringe, with exclusion of air, the solution is transferred into a cell comprising two glass plates with a PVC tube of external diameter 3 mm as spacer. After 18 hours at 7020 C. in a circulation oven, the methyl methacrylate has polymerized completely. The clear plate obtained in this way is cut into strips and employed for exposure experiments. On exposure under a mask using a 5000 W mercury high-pressure lamp at a distance of 80 cm, a dark blue negative image of the mask is obtained.

Examples B2-B5

Colour change systems as light indicators, photosensitizers and photoinitiators

Solutions comprising 100 g of technical grade epoxide-cresol novolak (epoxide value 4.5 eq/kg), 50 g of a technical grade bisphenol A diglycidyl ether (epoxide value 0.35 eq/kg), 30 g of Ultramix talc (cyprus), 180 g of cyclohexanone, 5.times.10.sup.-3 mol of the compounds according to the invention listed in Table 4, and 4 g of (.eta..sup.6 -cumene)(.eta..sup.5 -cyclopentadienyl)iron(II) trifluoromethanesulfonate are applied to a circuit board using a wire doctor blade. The initially wet film is dried at 80.degree. C. Exposure of the plates produced in this way is carried out using a 5000 watt mercury-high pressure lamp at a distance of 50 cm from the superimposed mask (Stouffer wedge). The exposure time is 1 minute. The plate is then pre-cured at 110.degree. C. for 10 minutes. The development is carried out in cyclohexanone, the unexposed areas (solder eyes) being dissolved. The plates are then post-cured at 135.degree. C. for 30 minutes. The plates obtained in this way are dipped into a solder bath (270.degree. C.) for 10 seconds, during which no changes are observed.

The colour changes and the final wedge step of the Stouffer wedge (FWS) to be imaged are shown in Table 4.

TABLE 4______________________________________ CompoundExample fromNo. Example Colour change FWS______________________________________B2 A69 Colourless/cyan 7B3 A70 Colourless/violet 8B4 A7 Colourless/violet 10B5 A93 Colourless/green 10______________________________________

Examples B6-B74

The suitability of these materials is tested in two formulations of photosensitive offset plate coatings:

Formulation I contains on the compounds according to the invention and no additional sensitizer.

It comprises:

1) 2.50 g of a copolymer comprising 86 parts by weight of 6-(dimethylmaleinimidyl)hex-1-yl methacrylate and 14 parts by weight of methacrylic acid (40% by weight in methoxypropanol), M.sub.w : 100,000 2) 5.00 ml of the compound according to the invention (1% by weight in dimethylformamide) 3) 0.50 ml of Rhodamine B (dye), 1% by weight in ethylcellulose 4) 2.50 ml of ethyl glycol acetate.

Formulation II contains, in addition to the compounds according to the invention, an additional, commercially available sensitizer.

1) 2.50 g as in formulation I 2) 2.50 ml of the compound according to the invention (2% by weight in dimethylformamide) 3) 2.50 ml of dioctyl 3,4-thioxanthonedicarboxylate, 2% by weight in dimethylformamide 4) 0.50 of Rhodamine B, 1% by weight in ethylcellulose 5) 2.50 ml of ethyl glycol acetate

The formulations are applied to an offset plate substrate, i.e. aluminium sheet which has been electrolytically roughened and anodized, by spin coating (30 seconds at 500 rpm), and dried at 80.degree. C. for 15 minutes, giving a coating weight of 1.1-1.5 g/m.sup.2. The coating is then exposed through a Stouffer wedge (increments of optical density O.D.=0.15) using a 2000 watt metal halide lamp for 100 seconds (distance 75 cm from the vacuum frame). Development is carried out manually at 20.degree. C. by gentle rubbing for 45 seconds with a wad soaked in the following developer solution:

75.0 g of sodium metasilicate pentahydrate 0.4 g of wetting agent (Supronic B 50, ABM Chemicals Ltd.) 925.0 g of demineralized water.

The plates are briefly rinsed with tap water and allowed to dry, and the photosensitivity is then assessed by determining the final wedge step of the numbered Stouffer wedge (FWS) to be imaged. The more wedges steps imaged at a certain exposure energy, the higher the photosensitivity of the coating.

Virtually all the formulations used here give offset printing plates of high photosensitivity and good abrasion resistance, which permits large print runs.

The results are shown in Table 5. The quality of the colour change directly after exposure is given a grade:

1=image poorly visible 2=image readily visible 3=image very readily visible.

The duration in time of the image (image stability) was also assessed by carrying out a qualitative check after 1 hour and after 24 hours for any fading of the image.

TABLE 5__________________________________________________________________________Compound Formulation I Formulation IIExample from Image stability Image stabilityNo. Example No. FWS Colour change (h) FWS Colour change (h)__________________________________________________________________________B6 A92 10 3 1 10 3 1B7 A9 7 2 24 9 2 24B8 A67 5 1 24 8 1 24B9 A95 10 3 24 10 3 24B10 A68 7 1 24 9 1 24B11 A69 7 1 24 8 1 24B12 A70 6 1 24 8 1 24B13 A71 9 2 24 9 2 24B14 A92 11 2 24 9 2 24B15 A66 7 1 24 10 1 24B16 A78 9 2 24 9 2 24B17 A79 7 2 24 9 2 24B18 A80 3 1 24 7 1 24B19 A73 6 1 24 9 2 24B20 A74 5 2 24 9 2 24B21 A35 8 2 24 10 2 24B22 A36 7 1 24 10 1 24B23 A37 7 2 24 9 2 24B24 A38 7 2 24 9 2 24B25 A39 6 2 24 9 2 24B26 A40 6 2 24 9 2 24B27 A41 6 2 24 8 2 24B28 A42 0 1 24 7 1 24B29 A43 0 1 24 5 1 24B30 A44 7 2 24 9 2 24B31 A45 6 2 24 8 2 24B32 A46 6 2 24 8 2 24B33 A47 7 2 24 8 2 24B34 A48 7 2 24 9 2 24B35 A49 8 2 24 9 2 24B36 A6 8 3 24 9 3 24B37 A34 4 1 1 7 1 1B38 A33 6 2 24 8 2 24B39 A84 6 1 24 8 1 24B40 A34 9 2 24 9 2 24B41 A50 6 2 24 8 2 24B42 A51 8 2 24 10 2 24B43 A52 7 2 24 8 2 24B44 A53 5 2 24 8 2 24B45 A54 6 2 24 7 2 24B46 A58 7 2 24 9 2 24B47 A59 8 2 24 9 2 24B48 A55 6 2 24 7 2 24B49 A57 8 2 24 8 2 24B50 A60 6 2 24 8 2 24B51 A61 6 2 24 9 2 24B52 A62 7 2 24 8 2 24B53 A63 0 2 24 6 2 24B54 A64 4 1 24 7 1 24B55 A12 9 2 24 9 2 24B56 A13 8 2 24 9 2 24B57 A14 5 2 24 8 2 24B58 A15 6 2 24 8 2 24B59 A16 9 2 24 9 2 24B60 A17 5 2 24 8 2 24B61 A18 8 3 24 9 3 24B62 A19 7 2 24 9 2 24B63 A20 8 2 24 9 2 24B64 A21 5 2 24 8 2 24B65 A22 8 2 24 9 2 24B66 A23 9 2 24 9 2 24B67 A24 7 2 24 9 2 24B68 A25 5 2 24 8 2 24B69 A26 8 3 24 8 3 24B70 A27 4 2 24 7 2 24B71 A85 8 3 24 9 3 24B72 A29 9 3 24 10 3 24B73 A97 6 2 24 8 2 24B74 A30 9 3 24 10 3 24__________________________________________________________________________

Claims

1. A radiation-sensitive composition which is photochromic and which comprises

(a) a radiation-sensitive organic material, and

(b) a photochromic compound of the formula I ##STR22## in which X is O, S, SO, SO.sub.2 or NR.sub.13,

R.sub.1 to R.sub.5, independently of one another, are H, C.sub.1 - C.sub.12 alkyl, C.sub.1 -C.sub.12 alkoxy, C.sub.1 -C.sub.12 alkylthio, C.sub.1 -C.sub.4 alkyl--SO--, C.sub.1 -C.sub.4 alkyl--SO.sub.2 --, halogen, CF.sub.3, --CN, --NO.sub.2, --OH, --COOR.sub.14, --CON(R.sub.15).sub.2, or --N(R.sub.15).sub.2, or the radical of the formula ##STR23## in which R.sub.16 and R.sub.17, independently of one another, are C.sub.1 -C.sub.6 alkyl, phenyl, C.sub.1 -C.sub.6 alkylphenyl or (C.sub.1 -C.sub.6 alkyl).sub.2 -phenyl, or R.sub.3 and R.sub.4 or R.sub.4 and R.sub.5, in each case together, are --CH.dbd.CH--CH.dbd.CH--,

R.sub.6 to R.sub.12, independently of one another, are H, C.sub.1 -C.sub.12 alkyl, C.sub.1 -C.sub.12 alkoxy, C.sub.1 -C.sub.12 alkythio, C.sub.1 -C.sub.12 alkyl--SO--, C.sub.1 -C.sub.12 alkyl--SO.sub.2, benzyl or C.sub.1 -C.sub.4 alk-1-yl which is 1-substituted by a total of one or two --CN and/or --COOR.sub.14, phenyl, phenyl-C.sub.1 -C.sub.4 alkylene, phenyl--CO--, phenyloxy, phenylthio, phenyl--SO--, phenyl--SO.sub.2 --, benzyloxy, benzylthio, benzyl--SO--, benzyl--SO.sub.2 --, C.sub.1 -C.sub.18 acyl--O--, --COOR.sub.14, --CON(R.sub.15).sub.2, C.sub.1 -C.sub.18 acyl--NR.sub.15 --, (R.sub.15).sub.2 N--, halogen, --CF.sub.3 or --CN, or each two adjacent radicals of R.sub.6 to R.sub.12 are the groups --CO--O--CO-- or --CO--NR.sub.13 --CO--, the phenyl radicals and radicals containing phenyl groups being unsubstituted or substituted by halogen, --CN, --CF.sub.3, C.sub. 1 -C.sub.6 alkylthio, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkyl, --COOR.sub.14, --CO--N(R.sub.15).sub.2 or C.sub.1 -C.sub.12 acyl--O--,

R.sub.13 is H, C.sub.1 -C.sub.12 alkyl or C.sub.1 -C.sub.12 acyl, phenyl or benzyl, which are unsubstituted or substituted by C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkylthio, halogen or --COOR.sub.14,

the two R.sub.15 together are C.sub.4 -C.sub.8 alkylene, 3-oxa-1,5-pentylene, 3-thia-1,5-pentylene, 1,3-butadiene-1,4-diyl or 2-aza-1,3-butadiene-1,4-diyl, or the R.sub.15 radicals, independently of one another, are H, C.sub.1 -C.sub.12 alkyl, or phenyl or benzyl which is unsubstituted or substituted by C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkylthio, halogen or --COOR.sub.14, and

R.sub.14 is phenyl, (C.sub.1 -C.sub.4 alkyl)phenyl, benzyl, 1-phenyleth-2-yl, benzyl or 1-phenyleth-2-yl substituted by 1 or 2 C.sub.1 -C.sub.12 -alkyl, C.sub.1 -C.sub.20 -alkyl, C.sub.3 -C.sub.8 -cycloalkyl, C.sub.3 -C.sub.8 -polyoxaalkylene radical of the formula --(C.sub.n H.sub.2n --O--).sub.m R.sub.18, in which n is an integer from 2 to 4, m is a number from 1 to 12, and R.sub.18 is C.sub.1 -C.sub.18 -alkyl, C.sub.3 -C.sub.8 -cycloalkyl, C.sub.5 - or C.sub.6 -cycloalkylmethyl, phenyl, benzyl, or phenyl or benzyl, substituted by 1 or 2 alkyl groups having 1 to 12 carbon atoms.

2. A composition according to claim 1, in which, in the formula I, R.sub.1 to R.sub.5, independently of one another, are H, C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, halogen, --CF.sub.3, --CN, --NO.sub.2, --COOR.sub.14, --OH, or --N(R.sub.15).sub.2, or R.sub.3 and R.sub.4 or R.sub.4 and R.sub.5, in each case together, are --CH.dbd.CH--CH.dbd.CH--, each R.sub.15 is C.sub.1 -C.sub.6 alkyl, and R.sub.14 is linear or branched C.sub.1 -C.sub.18 alkyl.

3. A composition according to claim 2, in which, in the formula I, at least 2 of the radicals R.sub.1 to R.sub.5 are H.

4. A composition according to claim 1, in which in the formula I, R.sub.6 to R.sub.12, independently of one another, are H, C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkylthio, C.sub.1 -C.sub.6 alkyl--SO--, C.sub.2 alkyl which is 1-substituted by a total of one or 2-CN and/or COOR.sub.14, phenyl, phenyl-C.sub.1 -C.sub.4 alkylene, phenyl--CO--, phenyloxy, phenylthio, phenyl--SO--, benzyloxy, benzylthio, benzyl--SO--, benzyl--SO.sub.2 --, C.sub.1 -C.sub.8 acyl--NR.sub.15 --, --COOR.sub.14, --CON(R.sub.15).sub.2, (R.sub.15).sub.2 N--, --F, --Cl, --Br, --CF.sub.3 or --CN or each two adjacent R.sub.6 to R.sub.12 radicals together are --CO--O--CO-- or --CO--NR.sub.13 --CO--,

R.sub.13 is C.sub.1 -C.sub.6 alkyl, or phenyl or benzyl which are unsubstituted or substituted by C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, F, Cl, Br or --COOR.sub.14,

R.sub.14 is H, linear or branched C.sub.1 -C.sub.18 alkyl, phenyl, benzyl or --C.sub.n H.sub.2n --O R.sub.18, where n is a integer from 2 to 6, and m is a number from 1 to 20, and R.sub.18 alkyl, cyclohexyl, phenyl or benzyl, and

R.sub.15 is C.sub.1 -C.sub.6 alkyl, or phenyl or benzyl which is unsubstituted or substituted by C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, --F, --Cl, --Br or --COOR.sub.14, or the two R.sub.15 radicals together are 1,4-butylene, 1,5-pentylene, 3-oxa-1,5-pentylene or 1,3-butadiene-1,4-diyl.

5. A composition according to claim 1, in which, in the formula I, at least two of the radicals R.sub.6 to R.sub.12 are H.

6. A composition according to claim 1, in which, in the formula I, R.sub.6 is H, --Cl, --Br or methyl.

7. A composition according to claim 1, in which, in the formula I, R.sub.9 is H or --Cl.

8. A composition according to claim 1, in which, in the formula I, R.sub.11 is H or --Cl.

9. A composition according to claim 1, in which, in the formula I, R.sub.10 and/or R.sub.12 is --Cl, --Br, unsubstituted or substituted phenoxy or --COO--(C.sub.1 -C.sub.12 alkyl).

10. A composition according to claim 1, in which, in the formula I, R.sub.6 is H, --Cl, --Br or methyl, or in which, in the formula I, R.sub.9 is H or --Cl, or in which, in the formula I, R.sub.11 is H or --Cl, or in which, in the formula I, R.sub.10 and/or R.sub.12 is --Cl, --Br, unsubstituted or substituted phenoxy or --COO--(C.sub.1 -C.sub.12 alkyl), or in which, in the formula I, R.sub.7 and/or R.sub.8 is H, --F, --Cl, --NO.sub.2, --CF.sub.3, --Br, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, phenyl--CO--, .alpha.-cyanobenzyl, C.sub.1 -C.sub.8 acyl-NR.sub.15 --, pyrr --COO--(C.sub.1 -C.sub.12 alkyl), or phenoxy, phenylthio or phenylsulfonyl, which are unsubstituted or substituted by --F, --Cl, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, --COOH or --COO--(C.sub.1 -C.sub.12 alkyl) together are ##STR24## and R.sub.13 is H or C.sub.1 -C.sub.6 alkyl.

11. A composition according to claim 1, in which, in the formula I, R.sub.13 is C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.8 acyl, or phenyl or benzyl which are unsubstituted or substituted by F or --COOR.sub.14, and R.sub.14 is H or C.sub.1 -C.sub.12 alkyl.

12. A composition according to claim 1, in which, in the formula I, R.sub.14 is H, C.sub.1 -C.sub.18 alkyl, --C.sub.n H.sub.2n --O H, phenyl, C.sub.1 -C.sub.6 alkylphenyl, benzyl, C.sub.1 -C.sub.6 alkylbenzyl or cyclohexyl, n is an integer from 1 to 6, and m is a number from 1 to 20.

13. A composition according to claim 1, in which, in the formula I, R.sub.15 is H, C.sub.1 -C.sub.6 alkyl, phenyl, benzyl, or the two R.sub.15 radicals together are tetramethylene, pentamethylele, 3-oxa-1,5-pentylene or 1,3-butadiene-1,4-diyl.

14. A composition according to claim 1, in which R.sub.1 to R.sub.5 are H or R.sub.1, R.sub.2, R.sub.4 and R.sub.5 are H and R.sub.3 is --CO.sub.2 C.sub.2 H.sub.5, R.sub.6 and R.sub.8 are Cl, and R.sub.7 and R.sub.9 -R.sub.12 are H, and X is NCH.sub.3 or N--n--C.sub.3 H.sub.7.

15. A radiation-sensitive composition which is photochromic and which comprises

(a) a colorless organic solvent, a transparent thermoset, thermoplastic or structurally cross-linked polymer, an organic galss or a composite glass, and

(b) a photochromic compound of the formula I ##STR25## in which X is O, S, SO, SO.sub.2 or NR.sub.13,

R.sub.1 to R.sub.5, independently of one another, are H, C.sub.1 - C.sub.12 alkyl, C.sub.1 -C.sub.12 alkoxy, C.sub.1 -C.sub.12 alkylthio, C.sub.1 -C.sub.4 alkyl--SO--, C.sub.1 -C.sub.4 alkyl--SO.sub.2 --, halogen, CF.sub.3, --CN, --NO.sub.2, --OH, --COOR.sub.14, --CON(R.sub.15).sub.2, or --N(R.sub.15).sub.2, or the radical of the formula ##STR26## in which R.sub.16 and R.sub.17, independently of one another, are C.sub.1 -C.sub.6 alkyl, phenyl, C.sub.1 -C.sub.6 alkylphenyl or (C.sub.1 -C.sub.6 alkyl).sub.2 -phenyl, or R.sub.3 and R.sub.4 or R.sub.4 and R.sub.5, in each case together, are --CH.dbd.CH--CH.dbd.CH--, R.sub.6 to R.sub.12, independently of one another, are H, C.sub.1 -C.sub.12 alkyl, C.sub.1 -C.sub.12 alkoxy, C.sub.1 -C.sub.12 alkylthio, C.sub.1 -C.sub.12 alkyl--SO--, C.sub.1 -C.sub.12 alkyl--SO.sub.2 --, benzyl or C.sub.1 -C.sub.4 alk-1-yl which is 1-substituted by a total of one or two --CN and/or --COOR.sub.14, phenyl, phenyl--C.sub.1 -C.sub.4 alkylene, phenyl--CO--, phenyloxy, phenylthio, phenyl--SO--, phenyl--SO.sub.2 --, benzyloxy, benzylthio, benzyl--SO--, benzyl--SO.sub.2 --, C.sub.1 -C.sub.18 acyl--O--, --COOR.sub.14, --CON(R.sub.15).sub.2, C.sub.1 -C.sub.18 acyl--NR.sub.15 --, (R.sub. 15).sub.2 N--, halogen, --CF.sub.3 or --CN, or each two adjacent radicals of R.sub.6 to R.sub.12 are the groups --CO--O--CO-- or --CO--NR.sub.13 --, the phenyl radicals and radicals containing phenyl groups being unsubstituted or substituted by halogen, --CN, --CF.sub.3, C.sub.1 -C.sub.6 alkylthio, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkyl, --COOR.sub.14, --CO--N(R.sub.15).sub.2 or C.sub.1 -C.sub.12 acyl--O--,

R.sub.13 is H, C.sub.1 -C.sub.12 alkyl or C.sub.1 -C.sub.12 acyl, phenyl or benzyl, which are unsubstituted or substituted by C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkylthio, halogen or --COOR.sub.14,

the two R.sub.15 together are C.sub.4 -C.sub.8 alkylene, 3-oxa-1,5-pentylene, 3-thia-1,5-pentylene, 1,3-butadiene-1,4-diyl or 2-aza-1,3-butadiene-1,4-diyl, or the R.sub.15 radicals, independently of one another, are H, C.sub.1 -C.sub.12 alkyl, or phenyl or benzyl which is unsubstituted or substituted by C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkylthio, halogen or --COOR.sub.14, and

R.sub.14 is phenyl, (C.sub.1 -C.sub.4 alkyl)phenyl, benzyl, 1-phenyleth-2-yl, benzyl or 1-phenyleth-2-yl subs by 1 or 2 C.sub.1 -C.sub.12 -alkyl, C.sub.1 -C.sub.20 -alkyl, C.sub.3 -C.sub.8 -cycloalkyl, C.sub.3 -C.sub.8 -cycloalkylmethyl, or a polyoxaalkylene radical of the formula --(C.sub.n H.sub.2n --O--).sub.m R.sub.18, in which n is an integer from 2 to 4, m is a number from 1 to 12, and R.sub.18 is C.sub.1 -C.sub.18 -alkyl, C.sub.3 -C.sub.8 -cycloalkyl, C.sub.5 - or C.sub.6 -cycloalkylmethyl, phenyl, benzyl, or phenyl or benzyl, substituted by 1 or 2 alkyl groups having 1 to 12 carbon atoms.

16. A composition according to claim 1, wherein the compound of the formula I is present in an amount of from 0.001 to 20% by weight, based on component a).

17. A composition according to claim 1, wherein the radiation-sensitive organic material is a1) a nonvolatile monomeric, oligomeric or polymeric substance containing photopolymerizable or photodimerizable, ethylenically unsaturated groups, a2) a cationically curable system or a3) photocrosslinkable polyimides.

18. A composition according to claim 17, wherein component a1) is a homopolymer or copolymer of acrylates, methacrylates or maleates whose ester groups contain a radical of the formula ##STR27## in which A is unsubstituted or hydroxyl-substituted, linear or branched C.sub.2 -C.sub.12 alkylene, cyclohexylene or phenylene, and R.sub.20 and R.sub.21, independently of one another, are Cl, Br, phenyl or C.sub.1 -C.sub.4 alkyl, or R.sub.20 and R.sub.21 together are trimethylene, tetramethylene or ##STR28##

19. A composition according to claim 17, wherein component a2) is an epoxide compound containing at least 2 epoxide groups in the molecule into which a photoinitiator has been incorporated.